Computer Fundamentals

Computer In Brief Fundamentals

First

Copyright©2016

Edition

Computer Fundamentals In Brief First Edition

COPYRIGHT © 2016 ALL RIGHTS RESERVED. THIS BOOK IS AVAILABLE FOR FREE. THE BOOK OR ANY PARTS THEREOF MAY NOT BE REPRODUCED IN ANY FORM, SOLD, OR PROFITING FROM— WITHOUT PRIOR WRITTEN PERMISSION OF THE AUTHORS. EDITOR: DR. AHMED SALLAM

AUTHORS: DR. AHMED SALLAM

DR. MOHAMED KHAMISS HUSSEIN DR. MOHAMED HAMED MOUSA DR. AHMED ELTAHAWY

DR. MAHMOUD ELGAYYAR

REVIEWED BY: DR. MAI EL-CHIHALY

COVER DESIGNED BY: DR. AHMED SALLAM

Original printing layout: 17cm X 24cm

PREFACE

This book was prepared to address the increasing interest in the computer

science and information technology discipline in Egypt and around the globe.

To satisfy rising demand for graduates with a strong foundation in this discipline, the book covers a variety of topics and fundamentals of computers, and is appropriate for undergraduates studying different majors.

This edition helps the reader to gain an understanding of how the computer

was built, and how it performs its basic operations. The reader will get a good

exposure to basic computer components, designs and technologies to be able to select and buy his/her own computer.

The book also covers different computer applications and highlights some

essential tools required for all computer users including Word-processing,

Spreadsheet and Presentation applications. Moreover, the book covers basic knowledge of networking to help the reader understand the nature of the

Internet and to draw his/her attention to important skills such as protecting privacy, searching online and validating information. Finally, the book

touches upon some advanced topics including Programming Languages, Web Design, Database, and Artificial Intelligence. III

Contents 1 History of Computing.....................................................................................10 1.1 Once upon a time ...................................................................................10 1.2 The Era of Gears ....................................................................................12 1.3 The Era of Electricity ..............................................................................16 1.4 Computer evolution ................................................................................19 1.4.1 Transistors .........................................................................................21 1.4.2 Memory..............................................................................................21 1.5 Memory evolution ...................................................................................24 1.6 Exercises................................................................................................25 1.7 References .............................................................................................26 2 Computer Hardware ......................................................................................30 2.1 What is a Computer? .............................................................................30 2.2 Types of Computers ...............................................................................30 2.3 Basic Microcomputer Hardware .............................................................33 2.3.1 The system unit .................................................................................33 2.3.2 The Motherboard ...............................................................................34 2.3.3 The Memory ......................................................................................34 2.3.4 The Microprocessor ...........................................................................35 2.3.5 Multicore CPU ...................................................................................37 2.3.6 The storage unit.................................................................................38 2.4 Input devices ..........................................................................................44 2.5 Output devices .......................................................................................46 2.6 How to buy a computer? ........................................................................49 2.6.1 Processor ..........................................................................................49 2.6.2 Memory (RAM) ..................................................................................50 2.6.3 Storage ..............................................................................................51 2.6.4 Dedicated graphics ............................................................................51 V

2.7 Exercises ............................................................................................... 51 2.8 References............................................................................................. 52 3 Computer Software ....................................................................................... 54 3.1 Operating Systems ................................................................................ 54 3.2 Application Software .............................................................................. 56 3.2.1 Desktop applications ......................................................................... 56 3.2.2 Security applications ......................................................................... 57 3.2.3 Internet applications .......................................................................... 57 3.2.4 Development tools ............................................................................ 58 3.3 Cloud services ....................................................................................... 59 3.4 Embedded systems ............................................................................... 59 3.5 Copyrights .............................................................................................. 60 3.5.1 Software license ................................................................................ 60 3.5.2 Free software .................................................................................... 61 3.5.3 Shareware software .......................................................................... 61 3.5.4 Modern Software stores .................................................................... 62 3.6 Recommended applications................................................................... 62 3.7 Exercises ............................................................................................... 63 3.8 References............................................................................................. 63 4 Computer Networking ................................................................................... 66 4.1 Internet ................................................................................................... 67 4.1.1 History ............................................................................................... 68 4.1.2 The TCP/IP Model ............................................................................. 70 4.1.3 IP Addresses ..................................................................................... 72 4.1.4 Static IP ............................................................................................. 74 4.1.5 Dynamic IP ........................................................................................ 74 4.1.6 Domain Name System ...................................................................... 75 4.2 Networks hardware ................................................................................ 75 4.2.1 Structured Cabling ............................................................................ 76 VI

4.2.2 Network Interface adaptor .................................................................77 4.2.3 Hub and Switch .................................................................................77 4.2.4 Routers ..............................................................................................78 4.2.5 Wireless Networks .............................................................................79 4.3 Networks Structure.................................................................................80 4.3.1 Peer-to-peer networks .......................................................................80 4.3.2 Client/server networks .......................................................................81 4.3.3 Network topologies ............................................................................83 4.4 Security & Privacy ..................................................................................84 4.4.1 Viruses and malware .........................................................................84 4.4.2 Network Security ...............................................................................85 4.4.3 Password protection ..........................................................................85 4.5 Online Searching Skills ..........................................................................87 4.5.1 Search Engines are just machines ....................................................87 4.5.2 Search Engines are not the only solution .......................................... 88 4.5.3 Organizing your search .....................................................................90 4.6 Judging online information .....................................................................91 4.6.1 Is Wikipedia reliable?.........................................................................93 4.6.2 Practice evaluating websites .............................................................93 4.6.3 Using multiple sources ......................................................................94 4.7 Exercises................................................................................................95 4.8 References .............................................................................................95 5 Advanced Topics...........................................................................................98 5.1 Programming Languages .......................................................................98 5.1.1 Problem decomposition .....................................................................99 5.1.2 Algorithm and Flow Chart ................................................................102 5.1.3 Programming languages .................................................................107 5.2 Web Programming ...............................................................................114 5.2.1 HTML (Hyper Text Markup Language) ............................................ 116 VII

5.3 Databases ............................................................................................ 122 5.3.1 Database Component ..................................................................... 123 5.3.2 Database people ............................................................................. 124 5.3.3 Database Management System (DBMS) ........................................ 125 5.3.4 Data Model ...................................................................................... 126 5.3.5 Database Architecture ..................................................................... 126 5.3.6 Database creation using SQL ......................................................... 127 5.4 Artificial Intelligence (AI) ...................................................................... 130 5.4.1 AI Techniques ................................................................................. 130 5.4.2 AI Applications ................................................................................ 131 5.5 Exercises ............................................................................................. 132 5.6 References........................................................................................... 133 6 Best Practice ............................................................................................... 136 6.1 Microsoft Word Tutorial ........................................................................ 136 6.2 Microsoft Excel Tutorial........................................................................ 144 6.3 Microsoft PowerPoint Tutorial .............................................................. 160 6.4 Exercises ............................................................................................. 170 6.5 References........................................................................................... 173

VIII

Chapter 1

History of Computing Dr. Ahmed Sallam

2016

COMPUTER FUNDAMENTALS

1 History of Computing If you have noticed, the title of this chapter is “history of computing”, not “history of computers”. In fact, no one who contributed to the history of computer industry had expected the current usages of computers. Their sole aspiration was to find a faster alternative performing mathematical operations, such as addition, and subtraction. Despite that, these simple operations themselves have gone through a long history which we are going to investigate in the following lines.

1.1 Once upon a time Certainly, the ancient man who practiced herding was assisted by a primitive system to count his cattle. Most likely, he was always carrying a bag with a number of pebbles matching the number of cattle’s heads he owned. Later, his needs led him to develop a simple counting system by inventing a set of operations such as addition and subtraction. However, addition and subtraction were not easy tasks at that time without numbers or a pen and a piece of paper. Thus, he improved his counting system by turning this bag of pebbles to a primitive counter drawn in the sand as a set of lines where pebbles are moved from line to another to perform various operations. After the spread of this technique, around 2400 BC the Babylonians lifted this method from the sand and turned the contours to wooden sticks attached to a wooden framework and transformed the pebbles into moveable beads installed

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in the sticks to make the first computer (Figure 1.1). It is known as Abacus or Abaci with respect to its old Turkish name [1].

Figure 1.1: Abacus

Surprisingly, this simple machine remained in use even after the appearance of the Arabic and Indian numbers. Moreover, some East Asian countries including China are still sticking to their use for this machine to enhance mental skills. With the development of numerical systems and the emergence of decimal numbers and fractions, the Abacus was not able to regulate all the operations. In the early seventeenth century, the Englishmen invented the Slide rule which was used in all the processes that we know so far from adding, subtracting and dividing integers and decimal numbers [2]. This tool has taken many forms, including rectangular (Figure 1.2) and circular (Figure 1.3).

Figure 1.2: Rectangular Slide Ruler


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Figure 1.3: Circular Slide Ruler

1.2 The Era of Gears Over time and with evolution, man was able to configure a set of gears to integrate and identify some of the information normally associated with geography and astronomy. For example, around 1110 BC Chinese people invented a simple tool called “the south-pointing chariot” (Figure 1.4) which was in the form of a cart carrying a man always spinning to point to the south [3].

Figure 1.4: The South-pointing Chariot

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100 years BC the Greek invented another tool called

“Antikythera mechanism” (Figure 1.5) which was used by astronomers to identify astronomical sites [4].

Figure 1.5: Antikythera Mechanism

The peak of human creativity in the use of gears was revealed in the golden age of Islamic civilization from the eighth century to the nineteenth century, where scholars developed various machines that were used in astronomy and other purposes. Ismail Al-Jazari crowned these inventions with an interesting tool called “Castle Clock” (Figure 1.6), which represented the first programmable machine reprogrammed to adjust the number of hours of day and night [5]. It has also been used to display Zodiac signs and identify motion of the sun and the moon. Moreover, Al-Jazari added some dazzling touches in the form of musical players response to different events. History of Computing

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Figure 1.6: Castle Clock

Since the seventeenth century better known as the era of machines, the idea of creating machine to perform mathematical operations was still a dream for many inventors. During this era, Pascal succeeded to invent a tool called Pascaline (Figure 1.7) in 1652 AD [6], which represented the first calculator approaching a fashionable form of calculators we are using nowadays. However, some mathematical operations needed a special procedure to be performed correctly in this machine.

Figure 1.7: Outer view of Pascaline

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Figure 1.8: Inner view of Pascaline

Again, the Pascaline was not enough to complete massive calculations and some operations were too complex to perform, such as multiplication and division. However, it was the nucleus for several machines that appeared later running similar systems. One of the most famous machines in that time was called “Curta” (Figure 1.9), designed by Curt Herzstark in 1938 [7]. The Curta was very small and could be held in one hand. Also, Curta was able to complete all the basic operations efficiently which helped it remain in use until the advent of the first electronic calculator in 1970. Nevertheless, it remained in use after that period.

Figure 1.9: Curta


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1.3 The Era of Electricity The man knew electricity since ancient times, but he learned many facts through the Kite experiment by Benjamin Franklin in 1752 [8]. One of these facts is that metals are good conductors, and that there is a relationship between lightning and electricity. Later, many scientists started to study electricity until it became part of our modern life after J. P. Morgan invested in the light bulb invented by Tomas Edison and started up the first power plant in 1882 in Manhattan, New York [9]. During this era, the dream of building a calculating machine still appealed to many scientists. They hoped to control this clean power that Tomas Edison handled to build his lamp. However, there were two obstacles to complete their dreams. The first obstacle was that electricity could be expressed by two values only (Negative and Positive) which was not suitable to represent the decimal system that includes ten distinct numbers (0 to 9). With research, scientists have found the solution to this problem has been existed for decades. Gottfried Leibniz adopted a new number system (Binary) in 1679 represented by two digits only, namely the one and zero [10]. The idea was to represent any decimal number with a binary number to simplify mathematical operations for massive calculations. For example, with 4 digits binary number you can represent the basic decimal numbers as follows: That was the key to overcome the first obstacle. Now we still have another challenge: how to adapt the electricity to get different values to represent all

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digits expressed in Table 1.1. Moreover, how can we perform calculations on these values? Table 1.1: Basic Decimal number representation in Binary

Decimal 0 1 2 3 4

Binary 0000 0001 0010 0011 0100

Decimal 5 6 7 8 9

Binary 0101 0110 0111 1000 1001

Scientists took on searching for a solution to this problem until they found that the solution had already been used in the Radio device in a circuit called “Vacuum Tube” (Figure 1.10).

Figure 1.10: Vacuum Tube

Vacuum Tube was the key to control the intensity of the current. This idea was revealed first in a scientific article published by C. E. Wynn-Williams in 1931 [11]. Later, Claude Shannon found a similar solution in the Telegraph device with a circuit called “Relay Switch” (Figure 1.11). History of Computing

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Figure 1.11: Relay Switch

That time, the road was paved to build the first electric-powered calculator. This dream became true in 1937 when Atanasoff and Berry created the first Model at the Iowa State College [12]. They completed building it in 1942 under the name “ABC”. However, ABC only designed to solve linear equations and can’t be reprogrammed. In the same period, probably in 1941, the German scientist Konrad Zuse built his first computer Z3 [13]. Z3 was a reprogrammable computer based on relay switches. However, It lacked many of the basic commands that must be met in a general computer, such as branch instruction which enable the programmer to execute the program instructions in a non-sequential order. This interesting story comes to its end with a brilliant design by John Mauchly and J. Presper Eckert for the first model of general purpose computers as we know it now (Figure 1.12). In 1964 Mauchly and Eckert with the help of a large group of scientists unbleached ENIAC (Electronic Numerical Integrator and Computer) at the University of Pennsylvania USA, funded by US military and contained 17,468 vacuum tubes [14]. 18



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Figure 1.12: ENIAC Computer

1.4 Computer evolution It is better to know some facts about the first computer ENIAC to understand the different stages of computer development. Basically, there were two main problems. First, ENIAC was weighing more than 30 tons, and Running into 167 square meters and consumed up to 150 kW, which had led to dim Philadelphia city whenever they needed to run it. It is interesting to realize that it was able to apply its calculations on numbers consisting of 10 digits only with speed up to 5000 cycles per second (very slow and limited compared to your mobile now). This fact can realized by adding two numbers such as 2 + 3 represented in Binary as follows (1 1 +1 0) then you need 3 Vacuum tubes working on a 6-volt large size battery, in addition to more than 4 small 9-volt batteries. This complex circuit (Figure 1.13) was just to half-add the given numbers. In other words, this was to add the first digit (0) of the binary form of 2 with the first digit 1 of the binary form of 3. History of Computing

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Figure 1.13: Half Adder

Consequently, if we need to run a program on ENIAC, we may need very complicated steps to be carried out by at least six people to control the large number of keys required for programming and reviewing the input/out, which could take up to two weeks. At that time, there was neither storage space nor memory to record the desired program and batch it to ENIAC. As a result, six girls (Figure 1.14) out of 200 were selected to work on ENIAC after a long training.

Figure 1.14: ENIAC Girls

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1.4.1 Transistors Later, the Transistors (Figure 1.15) came to the scene as a perfect alternative for Vacuum Tubes with smaller size and less power to rescue the city of Philadelphia. This start the second generation of computer production. It is believed that the first Transistor Computer was built at the University of Manchester in 1953 [15].

Figure 1.15: Transistors

With technological advances, it was possible to integrate millions of transistors on a single chip (Figure 1.16) which we call now IC (Integrated Circuits) this process continued until we reached to the current computers.

Figure 1.16: IC (Integrated circuits)

1.4.2 Memory A good solution to computer memory exists for a long time before computers. Around 1810, Herman Hollerith was in France to explore how punched cards were used to control Jacquard looms (Figure 1.18). He originated the idea of using holes punched in cardstock to control the pattern a loom weaves (Figure 1.17). Many Jacquard looms remain in use to this day, and you can occasionally find strings of Jacquard cards for sale [16]. History of Computing

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Figure 1.17: Jacquard Punched Card

Figure 1.18: Jacquard looms

Inspired by this technique Hollerith developed a new punched card to be used in statistical operations in the New York City Board of Health and several states. Later, he founded his company and developed these cards to be used for different accounting purposes. His company continued to develop these cards even after it was renamed to IBM, then in 1949 IBM produced the first CardProgrammed Electronic Calculator. 22



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It is worth mentioning that, the ABC computer model has used the idea of punched card first. The ABC design was illustrated in 1997 by building an identical replica of ABC by John Gustafson and his team in Ames Laboratory. The idea was simply to make circular holes within the card at certain positions to represent certain input (Figure 1.19), and use this card to buffer between a conducting surface and a roller with small movable pins (Figure 1.21). Whenever there is a hole, the pins were able to conduct the current and produce the desired inputs.

Figure 1.19: Punched Card Writer

Figure 1.20: Punched Card


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Figure 1.21: Punched Card Reader

1.5 Memory evolution With the increased need for memory that can accommodate a lot of inputs, computer developers started to search for a good alternatives to punched cards. J. Presper Echert and John Mauchly (the ENIAC creators) developed a brilliant idea after they established their new company. By using Magnetic tape, they produced a new computer (Figure 1.22) called UNIVAC 1 (UNIVersal Automatic Computer I) in 1951 [17]. In this computer, the input data was represented as negative and positive magnetic charges in an elastic magnetic tape similar to the Cassette tape. Since that time until now the development in this area began to widen and replace the magnetic tape by magnetic hard disks to spin faster.

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Figure 1.22: UNIVAC 1

Later, transistors were used again to build RAM (Random Access Memory) to retrieve data directly without the need to spin any surface at all. Currently, most of these technologies are still in use for different purposes.

1.6 Exercises 1. Castle clock designed by Al-Jazari was a good example of early mechanical computers. Write a short report to explain how it works. 2. Write a short report explaining how to convert from decimal to binary and how to perform ordinary operations such as summation with examples. 3. The early electronic computers were built based on multiple circuits called Vacuum tubes. Explain why these circuits where replaced later by Transistors. 4. Write a short report about the different kind of memories currently used in computers. History of Computing

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1.7 References [1] R. Bud and D. Warner, Instruments of Science: An Historical Encyclopedia (Garland Encyclopedias in the History of Science), 1st ed., Routledge, 1997. [2] E. G. Swedin and D. L. Ferro, Computers: The Life Story of a Technology, 1st, Ed., Johns Hopkins University Press, 2007. [3] J. Needham, Science and Civilisation in China: Volume 4, Physics and Physical Technology, Part 2, Mechanical Engineering, Cambridge University Press, 1965. [4] D. J. d. S. Price, Gears from the Greeks: Antikythera Mechanism - A Calendar Computer from c.80 B.C, Science History Publications, 1976. [5] H. R. Turner, Science in Medieval Islam: An Illustrated Introduction, University of Texas Press, 1997. [6] J. Falk, Things that Count, BY-NC-ND, 2914. [7] C. Stoll, The Curious History of the First Pocket Calculator, Scientific American, 2004. [8] J. L. Heilbron, Electricity in the 17th and 18th Centuries: A Study of Early Modern Physics, University of California Press, 1979. [9] M. Josephson, Edison, McGraw Hill, 1959. [10] Rudman and P. Strom, How Mathematics Happened: The First 50,000 Years, Prometheus Books, 2007. [11] C. E. Wynn-Williams, "The Use of Thyratrons for High Speed Automatic Counting of Physical Phenomena," in Proceedings of the Royal Society, 1991. [12] B. J. Copeland, "The Modern History of Computing," The Stanford Encyclopedia of Philosophy. [13] P. S. Trautman, A Computer Pioneer Rediscovered, 50 Years On, The New York Times, 1994. [14] W. T. Moye, ENIAC: The Army-Sponsored Revolution, US Army Research Laboratory, 1996. [15] E. Cooke-Yarborough, "Some early transistor applications in the UK," Engineering and Science Education Journal, vol. 7, no. 3, pp. 100-106, 1998. [16] M. Cambell-Kelly and W. Aspray, Computer: a history of the information 26



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machine, 2 ed., Basic Books, 2004. [17] L. Johnson, "Coming to grips with Univac," Annals of the History of Computing, IEEE, vol. 28, no. 2, pp. 32-42, 2006.


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Chapter 2

Computer Hardware

Dr. Mohamed Khamiss Hussein

2016


2 Computer Hardware This chapter presents the basic understanding of the computer architecture. It starts with the definition of the computer and introduces its types. Further, a detailed description of the computer hardware is introduced. The input, output and the secondary storage will be discussed. Finally, the chapter answers the most important question which is how to buy a computer.

2.1 What is a Computer? Computer is an electronic device which executes specific instructions that accept input, process the input, and produce meaningful information from the provided data, Figure 2.1.

Figure 2.1: A Computer System

2.2 Types of Computers There are four types of computers: supercomputers, mainframe, minicomputers, and microcomputers which are used according to different needs [1].

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Supercomputers are the most powerful and fastest type of computer. These machines are high-speed and high-capacity computers used by very large organizations. They are used for solving the world's most complex scientific and engineering problems, such as weather forecasting. IBM Blue Gene/P Supercomputer at Argonne National Laboratory is one of the world's most powerful, Figure 2.2.

Figure 2.2: IBM’s Blue Gene supercomputer.

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Mainframe are capable of great processing speeds and data storage, but are not nearly as powerful as supercomputers. For example, insurance companies use mainframes to process information about millions of policyholders.

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Minicomputers are medium-sized computers for departments of large companies typically use them for specific purposes. For example, production departments use minicomputers to monitor certain manufacturing processes and assembly-line operations.

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Microcomputers are the least powerful and the most widely used because it is the cheapest price type of computer. There are six types of microcomputers: desktop, media center, notebook, tablet PC, netbook, and handheld computers, Figure 2.3. Computer Hardware

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o Desktop computers are personal computers small enough to fit on top of or alongside a desk; yet are too big to carry around. o They usually consist of a monitor, keyboard, mouse and either a horizontal or vertical case which contains the hardware. o Media centers is a media personal computer which has less features than desktop computers and more features than dedicated entertainment devices such as home theaters. o Notebook computers, also known as laptop computers, are portable, lightweight, and can be carried around. o Tablet is a small portable computer that accepts input directly onto its screen rather than via a keyboard or mouse. The best known tablets are Apple’s iPad, Motorola’s Zoom, and Samsung’s Galaxy Tab. o Smart phones, also known as Handheld computers, are the cellphones which are designed to be held in the pocket and fit into the palm of one hand. These phones contain an entire computer system, including the electronic components, secondary storage, and input and output devices. Also, they are equipped with wireless connections to the Internet.

Figure 2.3: Types of Microcomputers

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Note: Mainframe and Minicomputers are historical names and currently called Servers and have the same purposes. However, they have different structure and usually used through networks or the internet.

2.3 Basic Microcomputer Hardware The basic microcomputer hardware consists of four basic categories: system unit, input/output devices, secondary storage, and communication [2].

2.3.1 The system unit Is a usually a tower-box container that contains the fundamental electronic components which make up a computer system. As seen in Figure 2.4, a typical system unit contains Motherboard, Memory and Microprocessor.

Figure 2.4: The system unit

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2.3.2 The Motherboard is a digital circuit board with connections for different components in a personal computer. The motherboard permits the equipment parts to trade information through printed wiring called bus.

Figure 2.5: Motherboard

2.3.3 The Memory The Memory is a holding area for data, instructions, and information. One type, random-access memory (RAM), holds the program and data that is currently being processed. This type of memory is sometimes referred to as temporary storage, or volatile storage, because its contents will be lost if the electrical power to the computer is turned off. Main memory, also called system memory, is the biggest amount of RAM introduced on the motherboard. It is utilized to run software applications and briefly store the information that is supplied by the user for processing. Each software requires a specific amount of memory to run efficiently. The Read Only Memory (ROM) is an uncommon sort of memory which contains all the data the PC needs to switch itself on, check that all its components are 34

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working correctly and to tell the PC what hardware components are connected at the motherboard. It is non-volatile which cannot be changed or overwritten, and continues to be saved even when the computer is switched off. The BIOS (Basic Input Output System) memory is an example of ROM on a PC which empowers the PC to start up and allows the integrated devices to communicate with each other [3].

2.3.4 The Microprocessor The microprocessor, or Central Processing Unit (CPU), is the brain of the computer. All the "thinking", calculating and processing is performed inside the CPU. The CPU also controls and process data to produce information and finally decides what to do with the results. The CPU is receives instructions from the user by running the user’s software. Many millions of instructions can be executed by the CPU per second. After executing the instructions, the results are transferred to other integrated connected components on the PC. The rate at which the CPU works can be the principal variable affecting the general performance of the computer. The CPU’s activities are coordinated by a clock that is used to synchronize all internal processes. Each unit of time is called a cycle and speeds are generally measured in Megahertz (MHz) or Gigahertz (GHz). 1 Megahertz = 1 million cycles per second. 1 Gigahertz = 1000 Megahertz.

The CPU consists of three main units, called Arithmetic and Logic Unit, Control Unit and register unit, Figure 2.6. The Arithmetic Logic Unit performs the different arithmetic and logic operations. The Control Unit fetches, decodes and Computer Hardware

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executes data from the memory. The register unit contains several fast data storage cells (similar to main memory cells), called registers, that are used for temporary storage of information within the CPU. For the purpose of transferring data, the CPU and the main memory are connected by a collection of wires called a bus. Through this bus, the CPU transfers data from main memory by specifying the address of the memory cell along with an electronic signal telling the memory circuitry that it is supposed to read the data in the specified cell. In a similar manner, the CPU stores, or writes, data in memory by providing the specific address of the destination memory cell and the data to be stored together with an appropriate electronic signal which tells main memory that it is supposed to store the data being sent in the specified memory cell.

Figure 2.6: CPU and main memory connected via a bus

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The CPU runs faster than any other components in the computer system. Therefore, an immediate access memory, called cache, is usually used as a buffer to maintain a consistent flow of the data to and from the CPU. The CPU requires a fan to keep it cool while the computer is on because the CPU’s often generate considerable amount of heat while it is working. There are two main manufacturers of CPU’s, Figure 2.7, Intel (Pentium and Celeron CPU’s), and AMD (K6, Athlon and Duron CPU’s). Each manufacturer releases faster and improved CPU’s quite often.

Figure 2.7: CPU manufacturers

2.3.5 Multicore CPU A Multicore processor is a single processor which has several cores on a single chip. The cores are computational units which are made up of several ALU units and caches. The individual cores on a multi-core processor don not necessarily provide a higher performance than single core processors, but they improve overall performance by handling several tasks in parallel at the same time. The enhanced performance can be seen by understanding the way in which a single core and multi-core processors execute programs. Single core processors Computer Hardware

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running multiple programs would assign a certain time slice to execute one program and then assign different time slices for the remaining programs. If one of the processes is taking longer time to complete then all the rest of the processes will be delayed. However, for multi-core processors, it can execute multiple tasks in parallel at the same time, each of them will be executed by an individual core in parallel thus the performance will be enhanced. The names of processors with different numbers of cores are as follows: Table 2.1: Names of multi-core processors

Number of cores 1 2 3 4 5 6 7 8 9 10

Common names single-core dual-core tri-core, triple-core quad-core penta-core hexa-core hepta-core octa-core, octo-core nona-core deca-core

2.3.6 The storage unit The data in the computer is represented in streams of bits, short for Binary digits. The bit is the smallest amount of data where the computer can understand and deals with. Each bit can be in one of two states either 1 or 0 (on and off). Eight bits are combined together in a set to form a byte. Bytes are used to represent several data types, such as numeric data and characters – for example, 01000001 is the character ‘A’ in binary ASCII code. Also, the binary codes are also used for coding the different instructions in the computer. Several other units 38

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are used to measure bigger amounts data, such as kilobytes, Megabytes and Gigabytes. A kilobyte (KB) is 1024 bytes. A kilobytes is usually used to measure the size of the files stored on the computer. A megabyte (MB) is 1,048,576 bytes (1024 kilobytes). A 1MB is approximately 5000 pages of double-spaced text. A gigabyte (GB) is 1,024 megabyte’s. A gigabyte is usually used to measure the capacity of devices such as hard drives or the amount of memory in the computer. Table 2.2: Storage unites

Bit

1 or 0

Byte

8 bits

Kilobyte (KB)

1024 Byte

Megabyte (MB)

1024 KB

Gigabyte (GB)

1024 MB

Terabyte (TB)

1024 GB

Computers requires hardware storages to store all the data such as music, videos, pictures, documents, spreadsheets, presentations, emails. Two different types of storage devices exist in a computer system called Primary storage and secondary storage. The primary storage is the internal temporary store directly accessible by the CPU that allows the CPU to process data faster. The primary storage is much smaller than secondary storage but much quicker to access because it has no Computer Hardware

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mechanical parts. Examples include RAM, ROM and the cache memory of the CPU. The secondary storage is not directly accessible by the CPU like the primary storage. Secondary storage is used for permanently storing data that is not currently being processed by the CPU. But the stored data may need to be accessed later, for example movies, pictures, the operating system files, documents, music files and emails. The secondary storage is non-volatile as the stored data remains saved even when the computer is switched off. The secondary storage takes longer time to access than the primary storage. However, it provide much larger space to store data than the space provided by the primary storage. A computer’s largest secondary storage device is the hard disk drive, also called hard drive. The current capacity of the hard disk would typically fall between 250GB (gigabytes) to 2TB (terabytes). Examples of the secondary storage include: Hard disk: The hard disk is normally fixed inside the computer’s system unit. It is used to stores large volumes of data which can be accessed and retrieved quickly at later time. The drive is composed of several magnetic disks in a protective casing. Data is recorded magnetically onto circular tracks which are partitioned into a number of sectors. An arm moves over the surface of the disk to read or writes the data. The location of tracks and sectors is not a permanent part of a disk’s physical structure. Instead, they are marked magnetically through a process called 40

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formatting (or initializing) the disk, usually performed by the disk’s manufacturer, resulting in what are known as formatted disks. Most computer systems can also perform this task. Thus, if the format information on a disk is damaged, the disk can be reformatted, although this process destroys all the information that was previously recorded on the disk. The capacity of a disk depends on the number of platters used and the density in which the tracks and sectors are placed. High-capacity disk, capable of holding many gigabytes, or even terabytes, consist of perhaps three to six platters mounted on a common spindle. Furthermore, data may be stored on both the upper and lower surfaces of each platter. Currently, the hard disk sizes range from 250GB to 2TB. Several measurements are used to evaluate a disk performance: (1) seek time which is the time required to move the read/write heads from one track to another); (2) access time which is the sum of seek time and rotation delay; and (3) transfer rate which is the rate at which data can be transferred to or from the disk. The seek time of a hard disk is much lower and the transfer rate much higher than any other type of disk drive. A solid-state disk (SSD) is a solid-state storage device that uses integrated circuit assemblies as memory to store data persistently. SSD technology primarily uses electronic interfaces compatible with traditional block input/output (I/O) hard disk drives. Additionally, new I/O interfaces, like SATA Express and M.2 have been designed to address specific requirements of the SSD technology Computer Hardware

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SSDs have no moving mechanical components. This distinguishes them from traditional electromechanical magnetic disks such as hard disk drives (HDDs). Compared with electromechanical disks, SSDs are more resistant to physical shock, run silently, have lower access time, and lower latency. However, SSDs are (as of 2016) still roughly four times more expensive per unit of storage than HDDs. Floppy disk drive: A floppy disk drive is an old technology like a hard disk, but with removable disks, called floppies, floppy disks or diskettes. Floppy disk is used to transfer small files from one PC to another, up to 1.4MB. Older floppies really were floppy, as they came in soft plastic or card cases. Some drives support 120MB floppy disks but these drives are not common and even more expensive and the diskettes cannot be read in a standard floppy drive. ZIP/JAZ drives are another type of floppy drive that use special disks instead of floppy disks. Zip disks can store up to 100 times as much as a floppy disk can store. While the JAZ disks can hold much more data. Currently, ZIP and JAZ disks space range from 100MB diskettes to 2GB. Flash Drives A common property of mass storage systems based on magnetic or optical technology is that physical motion, such as spinning disks, moving read/write heads, and aiming laser beams, is required to store and retrieve data.

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This means that data storage and retrieval is slow compared to the speed of electronic circuitry. Flash memory technology has the potential of alleviating this drawback. In a flash memory system, bits are stored by sending electronic signals directly to the storage medium where they cause electrons to be trapped in tiny chambers of silicon dioxide, thus altering the characteristics of small electronic circuits. Since these chambers are able to hold their captive electrons for many years, this technology is suitable for off-line storage of data. CD-ROM/DVD-ROM Drive: (Compact Disk – Read Only Memory) drives read data from CD’s that can hold up to 800MB’s of data. These disks are 12 centimeters (approximately 5 inches) in diameter and consist of reflective material covered with a clear protective coating. Information is recorded on them by creating variations in their reflective surfaces. This information can then be retrieved by means of a laser beam that detects irregularities on the reflective surface of the CD as it spins. Current standard sizes of the CDs are 650MB’s and 700MB’s. DVD-ROM (Digital Versatile Disk) drives can store up to 17 gigabytes of data and are designed for storing large sizes of multimedia files including music, video and multimedia files. Recently all computers are normally equipped with DVD-ROM drives as these drives can also read and write standard CD’s.

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CD-R, CD-RW, DVD-R and DVD-RW drives allow you to write, also often referred to as burn, your private files and data at CD’s or DVD’s. Both CD-R and DVD-R disks are Read-Only after burning and can be read in almost any CD and DVD drive. CD-RW and DVD-RW disks allow you to delete and overwrite (Re-Write) data and re-use the disks. However, the RW disks are more expensive.

2.4 Input devices An input device is any device which is used to supply information to a computer for processing as data or for the selection of commands, menus, or icons. Several devices exist in different technology, such as keyboard, mouse, light pen, touch screen, light pad and camera. Keyboard: This is used to supply, also called to input/enter, data into a computer. With a keyboard, you can enter commands, select menu options and enter data/values into the running software.

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Mouse: The mouse is used to point and click on items/icons/menu’s on the screen. A pointer on the screen moves as you move the mouse on the disk. If you press the mouse buttons while the pointer is on certain icons or buttons, you can activate commands, open menus, or execute programs. Light pen: A handheld pen-like photosensitive device that lets you draw directly onto the screen, or click on buttons and menus for the purpose of passing information to the computer. Touch screen is a display device similar to an ordinary TV screen allows the user to interact with a computer by touching areas on the screen. It has a thin, transparent layer of plastic covering that is touch-sensitive. When you touch a part of the screen, it has the same effect as if you clicked on that area with a mouse. Joystick: A hand-held stick which can be moved around in several direction to control an image on the computer. It is used mainly for playing games on the computer, for example, flight simulators and car racing. Touchpad is often used on laptops as an alternative to the mouse. With a touchpad, you can move the mouse cursor on the screen by touching the pad and moving your finger around. The two buttons, on the touch pad, simulate the use

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of the left and right buttons on a mouse. A touchpad works by sensing the user's finger movement and pressure. Trackerball is a computer cursor control device used instead of a mouse. The trackerball generally provides the same functionality as a mouse, however, you do not have to move the unit up/down/left/right in order to move the mouse pointer. You can just use your thumb on the rollerball to move the cursor on the screen easily. Graphics Pad is a graphics tablet, also known as a digitizer, drawing tablet, digital drawing tablet, pen tablet, or digital art board, It is mainly a computer input device that enables a user to hand-draw images, animations and graphics, with a special pen-like stylus, similar to the way a person draws images with a pencil and paper. It provides an easy way for drawing complicated shapes because a mouse is not always practical for such drawing. Scanner is an input device which is used to captures images and documents into a computer. It can be flatbed or handheld. Also, scanner is used for Optical Character Recognition (OCR) and to scan microfilm/transparencies and negatives.

2.5 Output devices The output devices are peripheral devices which receives the processed information from the processing unit in order to present it somehow to the user 46

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of computer. Current technology has been advanced to a phase where some devices are a combination of both input and output, such as a touch-sensitive screen. Output devices exist in a number of forms including monitor, printer, projector, speaker and plotter. A monitor is a bit similar to a television screen. The computer monitor displays visual output from the computer for text, movies and graphics. The monitors only offer temporary visual output as the displayed image is lost when power is switched off. Monitors can be standalone external devices, such as those LCD screen attached to PCs, or can be incorporated into the computer, such as laptops and notebooks. An external monitor can be upgraded or changed easily but a built-in monitor offers much less flexibility to change.The current technology has been advanced where the outdated substantial and cumbersome cathode-ray tube monitors (CRT) have been largely replaced by a better technology and much less bulky flatscreen technology including LCD and LED displays. The screen’s resolution is the number of pixels (dots) used to build a picture. Low number of pixels provides lower resolution and less image quality. High number of pixels provides higher resolution and better image quality. A printer is a device that prints output text and images on paper. Printing can be in color or ‘black and white’ depending on the used type of the printer. A several number of different types of printers are available Computer Hardware

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depending on the quality and the price. Laser: These are large, expensive printers that work like a photocopier. They usually have very high quality printouts and can print very fast. Inkjet: These are cheaper printers that use a little cartridge to spray a jet of ink onto the paper. They are fairly quiet and provide good quality, but are not as fast or produce such high quality as a laser printer. These printers are sometimes known as line printers because they print each page one line at a time. Dot matrix: An older type of printer that uses a ribbon and a print head, like a typewriter. They are very noisy and extremely slow. However, they are very much cheaper than any other printer. Plotter: This is a unique type of printer that draws pictures on papers based on commands from a computer. Plotters are used by engineers and designers who need to draw complicated diagrams. The plotter is used with a special software for engineering called CAD – Computer Aided Design. Speakers are external devices that attached to computers for the sound output. The sound output is produced by a sound card device. Speakers range from simple, single-speaker output devices offering low-quality sound to surround-sound multi-channel units which submit different output to multiple speakers in different locations in order to provide high quality sound. Headsets are a combination of speakers and microphones. Headsets are a very efficient method for the game player 48

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and communicating with friends and family over the internet using communication software, such as Skype and messenger. A projector is an output device that is used to project rays of light which translates the digital output into a visual display projected onto a large, flat surface.

2.6 How to buy a computer? As explained in the previous sections, there are many hardware which affect the performance of the computer such as processor, memory, cache and secondary storage. Each of them will be discussed in the following subsections.

2.6.1 Processor The processor is the brain of your computer. Although everyday computing, such as browsing the web, reading documents and watching movies, doesn't require a great deal of performance, a quicker processor is worth considering if you have enough money to pay. The power of the processors lies in the different number of integrated cores and the speed (labeled in GHz or Gigahertz) of each core. The speed of the processor revels how much data the processor can process in how much time. The higher the speed of the processor yields a better performance. The number of cores functions as a multiplier of the performance, as the processor is actually consists of number of cores that each run at a distinct speed.

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For example, a single-core 2GHz processor is a lot slower than a four-core 2GHz processor. Several cores can likewise improve the performance of the multi-tasking where each can be used to run a different task. If you don’t run a lot of softwares at the same time, you may be satisfied with only one or two cores, and there is no need to spend out the extra cash to get a higher number of cores. Make sure to know exactly how many cores are on the CPU and what the clock speed is of each core. Two computers might both have an Intel i5 processor, but the number of models that go into the group are numerous, and their speeds and number of cores can be largely different. Also, check out the cache size — the cache is the closest and fastest memory spaces to the CPU and the bigger the cache is the better. Processors like the Intel® i5 2GHz and AMD A8 make your computer boot quicker, open software faster and allow you to do many things at once, so are worth considering for regular users.

2.6.2 Memory (RAM) When you ask your computer to do something, the request goes to the memory (or RAM), where the processor picks it up and makes it happen. More memory lets the processor take on more at once, so you can download, chat, browse, work and listen to music at the same time without worry. 8 GB is enough for everyday computing, but you should consider 16 GB or more if you find your current computer slows down a lot. 50

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2.6.3 Storage The hard drive is where you save your documents, software, media and information. 500 GB is plenty for general use, while a 1 TB hard drive (twice the capacity of a 500 GB drive) is ideal if you plan on saving films, music and photos.

2.6.4 Dedicated graphics Dedicated graphics improve the way your PC displays videos, images and games. If you’re going to be editing photos, a dedicated graphics card can provide more natural colors and greater detail for much more accurate results. Dedicated graphics are essential for video editing and design work, as most industry standard software won’t run properly without increased graphics performance. Look for PCs with NVIDIA GeForce GTX or AMD R9 graphics for vastly improved visual performance.

2.7 Exercises 1. Describe the different types of computers. 2. What are the basic microcomputer hardware? 3. What are the differences between RAM and ROM? 4. What are the components of the CPU? 5. What is the difference between a single core processor and multi-core processor? 6. What is the difference between primary storage and secondary storage? 7. Give examples of different secondary storage. 8. What is the difference between Input and output devices? Computer Hardware

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2.8 References [1] T. O’Leary and L. O'Leary, Computing Essentials, 23th ed., McGraw-Hill/Irwin, 2013. [2] ICAP, Introduction to information technology, 1st ed., Emile Woolf International, 2013. [3] J. G. Brookshear, Computer Science: An Overview, 11th ed., AddisonWesley, 2011.

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Chapter 3

Computer Software Dr. Ahmed Sallam

2016


3 Computer Software If the hardware is considered the body of the computer, software is the spirit that makes it alive. The Software is a set of instructions that control the computer memory, processor and other resources. Basically, it is an ordered sequence of zeros and ones which translates to a negative and positive electrical charges for opening and closing various electric circuits within the computer to do a specific function as desired by the programmer. Software vary according to different functions as we will explain in the following lines.

Figure 3.1: A program in computer's memory

3.1 Operating Systems The operating system represents the main program that responsible for managing the various hardware resources and allows their sharing among other programs. Therefore, different programs stay working simultaneously with no problems which is known as Multi-tasking [1]. Operating system went through rapid development to turn into the current well known operating system used for laptop, and desktop computers such as

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Windows and macOS and other popular operating system built based on the concept of modern touch screens such as Android and iOS.

. Figure 3.2: Popular Desktop operating systems

Figure 3.3: Popular Mobile operating systems

Unlike Windows or macOS, there exist another great operating system called Linux. Linux is a free open source operating system comes with different distributions (distros) to suit different users tastes.

Figure 3.4: Different distros for Linux OS

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We can summarize the main tasks of operating system as follows: •

Manage the computer hardware resources. o CPU scheduling o Memory sharing o Input/Output (I/O) control

•

Control and protect other application programs.

3.2 Application Software Unlick operating systems, applications are different programs designed to complete a specific task [2]. Thus, without application software the computer still can function. We can divide applications based on their functions as follows:

3.2.1 Desktop applications Desktop applications are basic software applications required by most computer users such as calculator, utilities, word processing, spreadsheet, presentation and media applications. Most of these applications come with the operating systems. Some examples of these applications are: Word processing: Microsoft word for Windows environment, Open office for Linux environment, and another great cross platform called LyX. Media players: Windows media player, and VLC Player.

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3.2.2 Security applications Security applications are programs that used to detect malicious programs known as viruses from exploiting computer resources (memory/CPU) in unfair manners, and to prevent such programs from destroying important data. These applications commonly known as antivirus.

Figure 3.5: Popular antiviruses

Some security applications have different task and known as firewalls. Firewall is a software responsible for controlling the traffic of data entered or left the computer through the network/internet.

Figure 3.6: Popular firewalls

3.2.3 Internet applications This category covers every application depend on the Internet to complete its functions. A well-known example is the Internet browsers such as Chrome, and

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Firefox which used to browse websites. You can also extend the functionality of modern browsers by installing more extensions/plugins.

3.2.4 Development tools This category includes programming languages, design applications and development tools. Programming languages usually known as compliers and used to develop other software. There are many options based on the environment you need to deploy your new application on. Programming languages have different levels with respect to communication with the computer hardware. Low level programming languages interact directly with the computer hardware such as Assembly language and C language, while high level programming languages communicate with the hardware through the operating system such as Python, and Java.

Figure 3.7: Popular programming languages

Modern development tools perform more complex jobs and build enterprise applications and in the same time hide most of the code complexity from the developer. Some examples include database management systems such as Oracle, graphics design applications such as Unity, and web content management such as WordPress.

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Figure 3.8: Modern development tools

3.3 Cloud services Cloud services are the current trend for the new coming software revolution. Simply, the idea is to provide all possible applications as a services through the internet. One popular example is Google Docs which represent a complete online office suit run within your browser without buying or installing any application locally on your machine. Another example is Dropbox to replace your hard disk with a more reliable storage enable you to access your important files from any ware.

Figure 3.9: Cloud services

3.4 Embedded systems Embedded systems are usually fixed programs (operating systems) designed for specific machines such as your car GPS or your washing machine program. These applications designed for special purposes and you may need to change the hardware if you want to upgrade it in the future [3]. Computer Software

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Figure 3.10: Embedded system

3.5 Copyrights A good definition of Copyrights is: “A legal right created by the law of a country that grants the creator of an original work exclusive rights for its use and distribution. This is usually only for a limited time. The exclusive rights are not absolute but limited by exceptions to copyright law, including fair use.” [4] Registering a copyright for your original work protect your idea and your possible profit from this work. In software world, copyrights are usually managed through different licenses as we are going to explain next.

3.5.1 Software license Software license is an agreement between the developer and the user to control using the software. With the development of software industry, software license has also been developed and took many forms. We are going to cover popular license in the following lines.

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3.5.2 Free software Free software are authorized to be used by the users for free. The program creator may gain profit by different means such as donations, customers support, or advertisements. Usually, computer user get confused between free software and open source software. However, with open source software the source code of the program is available for everyone to edit and recreate a new software with more features, this usually known as Copyleft such as The GNU General Public License (GPL) . In the past, the two terms were conjoined, but now free software is not necessary an open source.

Figure 3.11: GBL logo

3.5.3 Shareware software Shareware software, is to offered a proprietary software to users also for free. However, the software usually is available for free with limited in functionality or be time-limited, and will continue to remind the user to upgrade for full functionality.

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3.5.4 Modern Software stores With the development of mobile phones and tablets a new concept of software marketing where emerged called application store. This store represent one place for all developers to share their products. The store providers developed especial application to communicate with the store and provide easy manners to find and update applications. Good examples for software stores are Google Play and iTunes from Apple.

Figure 3.12: App stores

3.6 Recommended applications In the following list we summarize some applications which can help you through your studying and researches. Table 3.1: Recommended applications for Scholars

Application

Description

LyX

Scientific writing

Mendeley

Reference manager and research articles sharing

Picasa

Photo editing application

MS-Expression

To Capture your desktop and record your presentation

Encoder Lingoes

62

Free dictionary and full text translation software

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3.7 Exercises 1. What is software? 2. What is the difference between Operating systems and Application software? 3. What are the main tasks of Operating Systems? 4. Give three examples of Application software. 5. Give two examples of mobile Operating Systems. 6. What is software license? 7. What is the difference between Freeware and Shareware applications? 8. What is the difference between Copyright and Copyleft? 9. What do “Cloud services” mean? 10. What is the difference between low-level programing and high-level programming?

3.8 References [1]

Stallings, Operating Systems, Internals and Design Principles, Pearson: Prentice Hall, 2005.

[2]

M. Oak, "For All the Tech Freaks: Different Types of Application Software," 2016. [Online]. Available: http://www.buzzle.com/articles/different-types-ofapplication-software.html.

[3]

S. Heath, Embedded systems design, 2ed ed., Newnes, 2003.

[4]

R. J. Dowd, Copyright Litigation Handbook, Thomson West, 2006.

[5]

C. J. Koo and J. Kim. [Online].

[6]

E. S. Agency, "COPYRIGHT AND SOFTWARE," [Online]. Available: http://www.esa.int/About_Us/Law_at_ESA/Intellectual_Property_Rights/Cop yright_and_software.

[7] M. Rouse and R. Lebeaux, "software license," http://searchcio.techtarget.com/, 2014.

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Chapter 4

Computer Networking Dr. Mohamed Hamed Mousa

2016


4 Computer Networking In networking architectures, PCs and other gadgets are associated with a sharing services. At the point, when a PC (or gadget) A is asking for a service from another PC (or gadget) B, A is mentioned as a client. Since all or most things that are a piece of a system live in affiliation or participation, all of them can be mentioned as clients. Taking into account this, there can be distinctive sorts of clients. A workstation is a PC on which a man performs ordinary normal tasks. A workstation is fundamentally a (PC). It can likewise be a tablet. Any current PC can be utilized as a workstation and take an interest to a system. The primary objectives of networking is to share services: •

You can play a CD music from another PC,

•

You may have a PC with a Compact disc/DVD/BD burner or an archiving framework yet the other computer(s) doesn't (don't) have it. For this situation, you can burn CD or make archiving on a PC that has one of these tools from a PC that doesn't have any burner or archiving framework,

•

You can interface a printer (or a scanner, or a fax machine) to one PC and let different PCs of the system print (or scan, or fax) to that printer (or scanner, or fax machine)

•

You can put some photos on one PC and let different PCs get to those photos

•

You can make documents and store them in one PC, then get to those records from alternate computer(s) associated with it.

•

You can share an internet connection.

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4.1 Internet The Web has reformed the PC and corresponding world like nothing some time recently. The development of the broadcast, phone, radio, and PC set the phase for this remarkable harmony of abilities. The Web is immediately an overall telecom ability, a system for data spread, and a medium for cooperation and connection amongst people and their PCs without respect for geographic area. The Web is at the top of standout amongst the best case of the advantages of managed investment and responsibility to innovative work. This is a critical point: The Web is a network of networks - not a network of hosts. The Web is the world's biggest network of networks. In the broadest terms, individuals like to view the Web as a cloud, you put your information in one spot, it turns out the spot you need it to on the opposite side. When you need to get to the assets offered by the Web, you don't generally interface with the Web. In fact, you associate with a system that is in the end associated with the Web spine, a system of greatly quick (and fantastically over-burden!) system segments. In all actuality the web is many thousands kilometers of fiber optic link, many thousands to a large number of kilometers of copper wire, and equipment and programming associating all of them together in a repetitive, quick, and independent system. Yet, not to stress, it isn't so much that awful: you just need to stress over a little section of the system, you can let another person stress over the rest, and you even motivate somebody to tell at when things turn out badly. Computer Networking

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4.1.1 History The Web was the consequence of some visionary deduction by individuals in the mid-1960s who saw extraordinary potential worth in permitting PCs to share data on innovative work in investigative and military fields. The Self-Automatic Ground Environment (SAGE) program comprised of arranged nationwide radar frameworks together interestingly. J.C.R. Licklider of MIT was chosen to head the advisory group which controlled the SAGE project. He initially presented a worldwide system of PCs in 1962, and moved over to the Defense Advanced Research Projects Agency (DARPA) in late 1962 to head the work to create it [1].

Figure 4.1: SAGE Computer Room

Licklider enlisted Lawrence Roberts to head a group which executed a system. Roberts had worked with the U.S. Air Force on a bundle exchanging framework instead of a circuit exchanging framework. On October 29, 1969, Licklider and Roberts interconnected the initial two hubs amongst UCLA and SRI at Menlo Park, 68

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California. This was the start of the Advanced Research Projects Agency Network (ARPANET) which was one of the key systems which our Web today was based on. Not long after the primary universal packet exchanged system administration was made between and U.K. Access to the ARPANET was extended in 1981 when the National Science Foundation (NSF) subsidized the Computer Science Network (CSNET). In 1982, the Web protocol (TCP/IP) was presented as the standard systems administration convention on the ARPANET. In the mid-1980s the NSF subsidized the foundation for national supercomputing focuses at a few colleges, and gave interconnectivity in 1986 the NSFNET venture, which likewise made system access to the supercomputer destinations in the Assembled States from exploration and instruction associations. Business Internet service providers (ISPs) started to develop in the late 1980s. The ARPANET was decommissioned in 1990. Constrained private associations with parts of the Web by formally business substances developed in a few American urban communities by late 1989 and 1990, and the NSFNET was decommissioned in 1995, expelling the keep going limitations on the utilization of the Web to convey business movement. Soon after, other business email administrations were soon associated, for example, OnTyme, Telemail, and Compuserve. Three Internet service providers (ISPs) were likewise made: UUNET, PSINET, and CERFNET. More separate systems were made that in the end interconnected with this substantial, developing system. The capability of TCP/IP to work over practically any previous correspondence systems took into account an incredible simplicity of development, despite the fact that the quick development of the Computer Networking

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Web was expected essentially to the accessibility of business switches from organizations, for example, Cisco Frameworks, proteon and Juniper, the accessibility of business Ethernet gear for neighborhood and the boundless execution of TCP/IP on the UNIX working framework. Despite the fact that the essential applications and rules that make the Web conceivable had existed for right around 10 years, the system did not increase open face until the 1990s. On August 6, 1991, CERN, which straddles the outskirt amongst France and Switzerland, promoted the new Internet venture. The web was designed by English researcher Tim Berners-Lee in 1989. An early well known web navigator was ViolaWWW. It was in the long run supplanted in prominence by the Mosaic web navigator. By 1996 use of "Web" had gotten to be typical, and subsequently, so had its utilization as a kind of perspective to the Internet. Throughout the decade, the Web effectively suited the barriers of existing open PC systems (however a few systems have stayed in isolation) [2].

4.1.2 The TCP/IP Model TCP/IP, “Transmission Control Protocol/Internet Protocol”, is the fundamental correspondence dialect or convention of the Web. “TCP/IP” characterizes an arrangement of rules to empower PCs to impart over a system. It can likewise be utilized as an interchanges convention as a part of a private system (either an intranet or an extranet). It determines how information ought to be designed, tended to, sent, steered and conveyed to the right destination. When you are set up with direct access to the Web, your PC is established with a duplicate of the TCP/IP program pretty much as each other PC that you may send messages to or 70

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get data from additionally has a duplicate of TCP/IP. There exist 5 levels in the TCP/IP paradigm [3]. The primary level is known as the “Physical Layer”. This level is in charge of encoding and transmitting information over network correspondences media. It works with information as bits which are sent from the Physical layer of the sending source and got at the Physical layer of a destination source. When you attach a PC utilizing an Ethernet link you are associating that PC on the Physical layer. This Physical layer is the most reduced level of the TCP/IP paradigm. The following level is the “Data link layer”. This layer is otherwise called “Network interface layer”. This layer typically comprises of corresponding drivers in the operating system and the network adapter connected to the framework. Both the component drivers and the system interface card deal with the correspondence subtle elements with the media being utilized to exchange the information over the system. In the greater part of the cases, this media is as cables. A portion of the popular conventions that are utilized at this layer incorporate ARP (“Address resolution protocol”), PPP (“Point to point protocol”) and so forth [4]. The following level is the “Network layer”. This layer is otherwise called “Internet layer”. The fundamental reason for this layer is to sort out or handle the transition of information on network. By transition of information, we for the most part mean directing of information over the network. The fundamental convention utilized at this layer is IP. While “ICMP” (utilized by famous "ping" service) and “IGMP” are likewise utilized at this layer. Computer Networking

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The following level is the “Transport layer”. This layer gives spine to information stream between sender and receiver. This layer gets information from the application layer above it. There are numerous conventions that work at this layer yet the two most regularly utilized conventions at transport layer are “TCP” and “UDP”. “TCP” is utilized where a trusted association is required while “UDP” is utilized as a part of instance of temperamental associations. The last level is the “Application layer”. This is the front layer of TCP/IP protocol. This layer incorporates applications or procedures that utilization transport layer conventions to convey the information to destination PCs. A portion of the wellknown application layer conventions are: •

“HTTP”, “Hypertext transfer protocol”

•

“FTP”, “File transfer protocol”

•

“SMTP”, “Simple mail transfer protocol”

•

“SNMP”, “Simple network management protocol”, etc

4.1.3 IP Addresses With the goal frameworks should find each other in a dispersed domain, PCs are given express addresses that remarkably recognize the specific network the framework is on and exceptionally distinguish the framework to that specific network. At the point when these two identifiers are consolidated, the outcome is a universally unique address [5]. This identification, referred to as “IP address”, as “IP number”, or simply as “IP” is a code made up of numbers isolated by three dots that recognizes a specific PC on the Web. This numbering is really 32-bit numbers, comprising of the two sub 72

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addresses (identifiers) said above which, individually, distinguish the system and the host to the system, with a fanciful limit isolating the two. An IP address is, accordingly, for the most part appeared as 4 octets of numbers from “0-255” spoke to in decimal structure rather than paired structure. For instance, the location

“168.212.226.204”

speaks

to

the

“32-bit”

binary

number

“10101000.11010100.11100010.11001100”. So what precisely does this number mean? The primary octet characterizes the class of the system. The class decides how enormous the addressing space is for the system. For example, what number of PCs can be tended to on the system. A class systems are the biggest, and are normally saved for governments. B class systems are second biggest, and are utilized by ISP's, enterprises, educational systems and so forth. C class systems are the littlest [6]. A = 0-123 (last 3 octets accessible for host and subnetting) B = 124-191 (last 2 octets accessible for host subnetting) C = 192 - 223 (last 1 octet accessible for host and subnetting) D/E = 224 - 255 (exploratory and testing systems) EXAMPLE: If your PC has an addressing of “158.59.224.135”, the location is translated as follows: The PC has a place with a class B, so the initial two octets characterize the system. The last two octets characterize the particular host on the system, and in addition any subnetting. The initial two octets are the IP address allocated by the ISP for the majority of the PCs in that system. The head or the client associates the last two octets to Computer Networking

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the PC. This implies you. If you have a system of, suppose, three PCs and your system IP location is “172.16.0.0” you can address the main PCs IP location to be “172.16.0.1” then the second PC's IP location can be “172.16.0.2”, and the third can be “172.16.0.3”. This permits you to keep your system somewhat more sorted out.

4.1.4 Static IP A static IP location is a number (as mentioned “quads”) that is associated to a PC by an “Internet service provider” (ISP) to be its changeless address on the Web. You will probably locate a static IP address on a server than on an individual PC. This is on the grounds that if the IP address to a server transforms it will disturb the capacity of clients to get to the site (or destinations) facilitated on that server.

4.1.5 Dynamic IP It would be straightforward if each PC that interfaces with the Web could have its own particular static IP number, however when the Web was initially considered, the designers didn't anticipate the requirement for a boundless number of IPs. Subsequently, there are insufficient IP numbers to go around. To overcome that issue, numerous access suppliers restrain the quantity of static IP addresses they provide, and reduce the remaining number of IPs they have by allocating, for a short time, an IP to an asking for “Dynamic Host Configuration Protocol” (DHCP) PC from a pool of IPs. The provisional IP is known as a dynamic IP address.

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4.1.6 Domain Name System The “domain name system” (DNS) is the way that Web space names are found and interpreted into Web IP addresses. A space name is an important and simple to-recollect "handle" for a Web address (ex: www.google.com.eg) into the corresponding IP addresses (ex: 216.58.194.163) which organizing hardware needs to receive data. DNS additionally stores other data, for example, the addresses of mail servers. DNS is a vital segment of the Web we utilize. Since keeping up a principal list of area name/IP address correspondences would be unrealistic, the arrangements of space names and IP locations are conveyed all through the Web in a hierarchical order. There is most likely a DNS server inside close geographic nearness to your entrance supplier that maps the space names in your Web asks for or advances them to different servers in the Web.

4.2 Networks hardware •

A PC network involves, all or partially, the next hardware set:

•

A least of no less than 2 PCs

•

Cables that interface the PCs to each other, even remote

•

A system interface component on every PC (this is known as an “interface card” or “NIC”)

•

A "Switch" used to change the information starting with one point then onto the next. HUBs are obsolete and are minimally utilized for new establishments.

•

Network framework programs

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4.2.1 Structured Cabling The two most prevalent sorts of organized system cabling are “twisted-pair” (otherwise called “10BaseT”) and coaxial (otherwise called “10Base2”). “10BaseT” cabling looks like common phone cable, with the exception of that it has 8 wires inside rather than 4. Coaxial resembles the “copper coaxial” cabling which is frequently used to interface a “Video Recorder” to a television. At the point when “10BaseT” cabling is utilized, a strand of cabling is embedded between every PC and a switch. In the event that you have 5 PCs, you'll need 5 links. Every link can't surpass 325 feet long. Since the links from the greater part of the PCs merge at a central point, a “10BaseT” system shapes like a star [7].

Figure 4.2: RJ45

“10BaseT” cabling is accessible in various evaluations or classes. A few evaluations, or "Cats", are required for Quick Ethernet systems, while others are flawlessly satisfactory for standard 10Mbps systems - and less costly, as well. Every single new system utilizes at least standard “unshielded twisted-pair” (“UTP”) Classification “5e 10BaseT” cabling in light of the fact that it offers an execution advantage over lower grades [8].

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4.2.2 Network Interface adaptor A “NIC” (proclaimed “nick”) is otherwise called a “Network interface card” and “LAN adapter”. It associates the PC to the cabling, which thus interfaces the greater part of the PCs on the system together. Every PC on a system must have a LAN adapter. Most present day cards are “10/100 NICs” and can work at either “10Mbps” or “100Mbps”. Just “NICs” supporting at least 100Mbps ought to be utilized as a part of new establishments understudies. PCs with a remote association with a system additionally utilize a corresponding wireless card.

Figure 4.3: Network Interface adaptor

4.2.3 Hub and Switch A “Hub” is a component used to interface a PC to the system. The capacity of this central component is to direct data around the system, encouraging correspondence between every single associated device. In any case, in new establishments switches ought to be utilized rather than hubs as they are more successful and give better execution. A switch, which is regularly named a “smart hub”, “Switches and hubs” are innovations or “boxes” to which PCs, printers, and other systems administration components are associated. “Switches” are the later innovation and the acknowledged method for building today's systems. With Computer Networking

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switching, every association gets “specified bandwidth” and can work at full speed. Interestingly, a hub offers data transfer capacity over numerous associations such that transmission from one PC or server can back off the compelling rate of different associations on the hub. Presently more reasonable than any other time in recent memory, Double speed “10/100 autosensing switches” are suggested for all university systems. students might need to consider replace any hub-based systems with switches to enhance system execution – i.e. accelerate data transmission on the system. The following are examples of 8-ports Hub, 16,24-ports switches separately.

Figure 4.4: Hub and two Switches

4.2.4 Routers Similar to a Hub, a “router” is another sort of hardware that goes about as the main issue among PCs and different gadgets that are a piece of a system. Here is an example of a wired router:

Figure 4.5: Router

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Router capacities are a little in contrast to a hub. In fact, a router can be viewed as somewhat “intelligent” than the Hub. Similar to a hub, the PCs and different gadgets are associated with a router utilizing system cables. To make this conceivable, a router is furnished with holes, called ports, in the back. Here is an example:

Figure 4.6: Router's Ports

In light of advances in the earlier years from IEEE and different associations or researchers, there are “wireless routers”. With this sort of routers, the PCs and other network components interface utilizing microwaves (no physical link).

4.2.5 Wireless Networks The terminology “'wireless network” alludes to two or more PCs imparting utilizing standard system rules or conventions, however without the utilization of cabling to interface the PCs together. Rather, the PCs use remote radio signs to send data from one to the next. A “wireless local area network” (WLAN) comprises of two key parts. (1) an “access point” (additionally called a “base station”) and a remote card. Data can be transmitted between these two parts the length of they are genuinely near one another (up to 100 meters inside or 350 meters outside). The following is an example of a wireless access point.

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Figure 4.7: Wireless Access Point

4.3 Networks Structure 4.3.1 Peer-to-peer networks “Peer-to-peer networks” are more generally actualized where under ten PCs are included and where strict security is not important. All PCs have the same status, consequently the terminology “peer”, and they inter-speak with each other on an equivalent balance. Records, for example, word preparing or spreadsheet reports, can be shared over the system and every one of the PCs on the system can share components, for example, printers or scanners, which are associated with any one PC. The following is an example of a peer-to-peer network.

Figure 4.8: Peer to Peer network structure

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4.3.2 Client/server networks “Client/server” or “master-slave” networking is more appropriate for bigger systems. A master PC, or “server”, goes about as the archiving area for documents and programs shared on the system. Normally the server is a higher than normal execution PC. The server likewise controls the system access of alternate PCs which are alluded to as the “client” or “slave” PCs. Ordinarily, instructors and students in a university will utilize the slave PCs for their work and just the system director (for the most part an assigned staff member) will have admittance rights to the server. The following is an example of a client-server network.

Figure 4.9：Client/ Server network structure

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COMPUTER FUNDAMENTALS Table 4.1: Peer-to-Peer Networks Vs Client/Server Networks

Peer-to-Peer Networks

Client/Server Networks

Simple to configure.

Not easy to configure.

Less costly to introduce.

More costly to introduce.

Can be actualized on an extensive An assortment of frameworks can be variety of working frameworks.

upheld on the slave PCs, yet the server needs to run a special framework that backings Networking.

Additional tedious to keep up the Less tedious to keep up the product product being utilized. (as PCs must be being utilized. (as the greater part of overseen individually)

the upkeep is overseen from the server)

Low levels of security upheld or none Abnormal amounts of security are by any means. These can be extremely bolstered, all of which are controlled bulky to set up, contingent upon the from the server. working framework being utilized.

Such measures keep the erasure of key framework documents or the changing of settings.

Perfect for systems with under 10 PCs.

No restriction to the quantity of PCs that can be bolstered by the system.

No need to have a master PC.

Need to have a master PC running a special framework.

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Requests a moderate level of ability to Requests that the system admin has an administrate the system.

abnormal background of administration skills with server framework.

4.3.3 Network topologies “Network topology” is to arrange the action of the different components of a PC networking. Basically, it is the layout structure of a system and might be delineated “physically or logically”. “Physical topology” is the arrangement of the different parts of a system, including component area and link establishment, while “logical topology” shows how information streams inside a system, paying little respect to its physical configuration. Separations between hubs, physical connectivity, transmission rates, or wave sorts may vary between two systems, yet their topologies might be indistinguishable [9]. The investigation of system topology perceives numerous fundamental topologies: “point-to-point”, “bus”, “star”, “ring or circular”, “mesh”, “tree” or “hybrid”.

Figure 4.10: Network topologies

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4.4 Security & Privacy 4.4.1 Viruses and malware “Malware” is short for malignant programming and utilized as a terminology to allude to “virus”, “spy ware”, “worm” and so on. Malware is intended to make harm a standalone PC or an arranged PCs. So wherever a malware terminology is utilized it implies a system which is intended to harm your PC it might be an “virus”, “worm or Trojan” [8]. Worms are vindictive routines that make duplicates of themselves over and over on the nearby drive, system services, and so on. The main motivation behind the worm

is

to

imitate

itself

over

and

over.

It

doesn't

hurt

any

information/document on the PC. Dissimilar to a virus, it doesn't have to connect itself to a current application. Worms spread by misusing vulnerabilities in working frameworks “Virus” is a routine composed to enter to your PC and harm/change your records/information. An infection may degenerate or erase information on your PC. Infections can likewise repeat themselves. A PC virus is more unsafe than a PC worm as it rolls out improvements or erases your records while worms just duplicates

itself

without

rolling

out

improvements

to

your

documents/information. “Trojans”: they are not viruses. It is a ruinous routine that looks as a trusted to original application. Dissimilar to virus, Trojan stallions don't reproduce themselves however they can be pretty much as ruinous. Trojans likewise open 84

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an indirect access section to your PC which gives malevolent clients/programs access to your profile, permitting private and individual data to be robbery.

4.4.2 Network Security System security comprises of the approaches and practices embraced to forestall and screen unapproved access, abuse, change, or denying of a PC system and system services. System security includes, accordingly, the approval of making a safe stage for PCs, clients and applications to play out their allowed basic capacities inside a protected situation. A home or little office may just require essential security while vast organizations may require high-upkeep and propelled programming and equipment to keep noxious assaults from hacking and spamming [10]. From taking a look at the sorts of infections that are regular, we can divine a generally short rundown of abnormal state rehearses that can anticipate security fiascos: •

You should have “Backups”.

•

Try not to put information where it doesn't should be.

•

Keep away from frameworks with sharp damages,

•

You should install important “security updates”.

•

Install a “Firewall”.

4.4.3 Password protection Clients pick or are provided with an “ID” and “Password” or other verifying data that permits them access to data and applications inside their profiles. It is very Computer Networking

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prescribed to maintain a strategic distance from normal or feeble secret words. If the word you utilize can be found in the lexicon, it’s not a solid secret key. In the event that you utilize numbers or letters as per the pattern in which they show up on the console (“1234” or “qwerty”), it’s not a solid secret word. In the event that it’s the nickname, or surname, of one of your family, your children, or your pet, most loved club, or your birthplace, and so on — it's not a solid secret word. In the event that it's your birthday, commemoration, graduation date, even your automobile tag number, it's not a solid secret word. It doesn't make a difference in the event that you tail this with another number. These are all things security attackers would attempt first. They compose projects to check these sorts of passwords to start with, indeed. Different terms to dodge: “god”, “cash”, “love”, “monkey”, “letmein”, in the event that you utilize “password” as your secret word, simply close down the Web at this moment. To make a solid secret word, you ought to utilize a string of content that blends numbers, letters that are both small and capitalized letters, and non-alphabetic characters. It ought to be eight characters, ideally some more. Significantly even more. The characters ought to be arbitrary, and not take after from words, one after another in order, or from your console design.

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4.5 Online Searching Skills Now, you can completely live online, do shopping, business, book tickets and make everything you can imagine. However, you need to online searching skills. Search engines are your best friends to help you with this [11]. Search engines are online services running over powerful machines to seek and record all available information on the internet which is called crawling and reorganized it in some sophisticated structure to simplify retrieving this information later, poplar search engines are Google, Yahoo, and Bing.

Figure 4.11: Popular search engines

To successfully

benefit from search engines

you need to remember the

following facts.

4.5.1 Search Engines are just machines Selecting your search keywords is the main factor to get what you are looking for. Actually, search engines don’t really understand the structure of your searching sentence, the engine just divide your sentence into a set of words and drop nonimportant word such as stop words, and then it starts to find a document include the biggest number of keywords you have provide.

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4.5.2 Search Engines are not the only solution The Internet has various type of web site including, Common websites types include, commercial, organization, news sites, schools, forums and blogs. It’s good idea to know that there are a lot of specialized sites to reach the information you needed directly without search. Here, we will try to cover a set of important websites to consider. Wiki : A wiki is a website category that allows any users to modify its content such as Wikipedia. The quality of the wiki topics depends meanly on the author and can be controlled through a set of volunteers to verify the references to this topic. Scholarly site For research and scientific fields, you can find scholarly work such as conference and journal articles using search engines such as Google Scholar and Thomson Reuters: Web of Science.

Figure 4.12: Google Scholar service

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Databases Different companies provide specialize Databases for different subjects such as Food, Movies, etc. One example is the Internet Movie Database (IMDb). Database is a well-organized information provide different options to search with.

Figure 4.13: IMDb movies database

Question & Answer sites Similar to forums, A question & answer sites enable a user to leave his questions and wait for the answers by other users. Unlick forums, a question & answer sites reorder the answers based on its quality considering other user opinions. Examples of question& answer sites include Yahoo Answers, Stack Overflow and Stack Exchange.

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Figure 4.14: Yahoo QA service

4.5.3 Organizing your search Part of retrieving desired information quickly based on your organization. A simple way to organize your online information is to use bookmarks in your web browser. Bookmarks help you to record your favorite links. However, remember that bookmarks only save the website link not the contents. Cloud-based bookmarking services Moreover, to reach your bookmarks from different machines, some providers offer online bookmark service. Technically we call this feature, Cloud-based bookmarking. The most popular bookmarking service providers include Google Bookmarks, Diigo, and Springpad.

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Figure 4.15: The Bookmark manager of Google Chrome

4.6 Judging online information The Internet has a lot of information. However, you can't trust everything you read. A good skill to learn is how to evaluate online information. The following questions can guide you to aid your evaluation skills [12] . Is the information relevant? If you are googling for some information, remember that not all the results relevant to what you actually looking for. Some sites appeared first just for advertisement. What is the site's purpose? Nowadays, many websites try to attract you just to promote some advertisement. Or trying to persuade you to buy some products. Computer Networking

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Figure 4.16: Misleading Advertisement

Is the site Hoax? To afford the internet, every web site must have a unique domain name consists of different parts. E.g. www.hotmail.com consists of Hotmail to present the service name and a top-level domain .com (commercial site). There are many more top-level domain such as .gov (government site), .org, and .edu. Whenever you open a link double check the top-level domain. “www.hotmail.com” is completely different from “www.hotmail.er.com”. You may receive some biased links similar to well-known websites just to fetch your personal information. Is the information reliable? The internet gives the chance to everyone to share information. However, among the chunk of articles you skim every day, only a few topics belongs to

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reliable organizations or individuals with good reputation . With time, you will create a list of reliable resources, so carefully add a new resource to this list. Is the information current? Always relate the news to the date it was released to take the right decisions.

Figure 4.17: Example to check news publishing date

4.6.1 Is Wikipedia reliable? Yes and No at the same time. Wikipedia is a good source of information to start with. However, remember that anyone can add or change information on Wikipedia, even if they don't know what they're talking about. Make sure to check the references at the bottom of an articles to evaluate this article correctly.

4.6.2 Practice evaluating websites You can follow some basic techniques to make a good judgment about online information.

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Use online service to evaluate information: Try to verify your information with specialized websites such as Snopes.com. This will help you in case your received a message like the following:

Figure 4.18: Example of Hoax messages

Use search by image to evaluate images: Google provide a Search by image service which could help you to know some facts about images such as, when it was published and who is the first publisher.

Figure 4.19: Google's search by image service

4.6.3 Using multiple sources It’s important to evaluate your information through multiple sources. Sometimes, it’s not a matter of reliability, but a matter of time. Using multiple resources help you to see the big picture.

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4.7 Exercises 1. 2. 3. 4. 5. 6. 7.

Explain the TCP/IP Model. What is meant by the dynamic and static IP? What is the role of the Domain name service? State the different types of connecting media in a computer network. Compare between the HUBs and the Switches? What is the role of the router inside a network? Compare between peer-to-peer network and client/server network in terms of: a. Scalability b. Security c. Cost d. Administration 8. Elaborate the different kinds of network topology. 9. Compare between each of the following: a. Virus b. Worm c. Trojan 10. What are the principle advices when creating a password?

4.8 References [1] W. B. a. J. Elkner, "Introduction to Information and Communication Technology," 2011. [2] B. M. Leiner, V. G. Cerf, D. D. Clark, R. E. Kahn, L. Kleinrock, D. C. Lynch, J. Postel, L. G. Roberts and S. Wolff, "Brief History of the Internet," http://www.internetsociety.org/. [3] V. G. Cerf and E. Cain, Computer Networks, North-Holland, 1983. [4] H. ARORA, "TCP/IP Protocol Fundamentals Explained with a Diagram," http://www.thegeekstuff.com/, 2011. [5] B. Forouzan, Data Communications and Networking, McGraw Hill, 2013. Computer Networking

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[6] "A SHORT INTRODUCTION TO IP ADDRESSES," Paessler AG. [7] I. FunctionX, "Network Hardware," 2005. [8] Bijay.Swain, "What are malware, viruses, Spyware, and cookies, and what differentiates them ?," http://www.symantec.com/, 2009. [9] D. Groth and T. Skandier, Network+ Study Guide, Sybex, Inc, 2005. [10] M. Curtin, "Introduction to Network Security," http://www.interhack.net/, 1997. [11] "Introduction to searching online," [Online]. Available: http://www.gcflearnfree.org/searchbetter/all-about-online-search/1/. [12] "How to judge online information," [Online]. Available: http://www.gcflearnfree.org/searchbetter/judging-online-information/1/.

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Chapter 5

Advanced Topics

Dr. Ahmed Eltahawy

2016


5 Advanced Topics "Computers are meant to make life easier". This is a statement that becomes a reality these days. Computers are now used to accomplish many tasks in a quick and easy way. Starting from everyday life such as paying bills and online shopping to more sophisticated uses such as online banking, patient portals, and countless applications that require secure web applications along with back-end databases. Moreover, computers are geared toward supporting a more luxurious lifestyle through high-end technologies like self-driving cars and robots that may assist humans in their daily work through efficient use of artificial intelligence techniques. In this chapter, the basic information about computer programming, web design, databases and artificial intelligence will be introduced. In Section 5.1, the basic concepts of computer programming including problem decomposition, flow chart, algorithm design and a quick introduction to computer programming are introduced. In Section 5.2, the meaning of web design, and the state-of-the-art in web programming are described. In Section 5.3, the basic idea and components of a database are explained. Finally in Section 5.4, the meaning and the applications of artificial intelligence techniques are presented.

5.1 Programming Languages Computer programming is simply the process of generating a computer program that is used to solve a certain problem. For example, the program that calculates the maximum number between three different numbers. The problem is to find 98

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the maximum between any three numbers. A program that solves this problem will accept the three numbers as inputs and then produce the maximum of them as output. Therefore, the program consists of input, calculation then output. The program is written using a programming language. This language is known by programmers and understood by the computer [1]. In general, a programmer is using a programming language to write a program that solves a certain problem. The process of generating an excitable program is process as follows: •

Understand and analyze the problem (problem decomposition).

•

Develop different solutions (algorithms)

•

Select the best algorithm

•

Implement the deleted algorithm using a programming language (Coding).

In this section, we will talk about the problem decomposition, the flow chart, the algorithm design and the programming languages.

5.1.1 Problem decomposition The first step in the computer program generation process is to understand the problem. Typically, a complex problem should be decomposed into a set of smaller problems; each of which is treated alone. This decomposition facilitates understanding, programming and maintaining a number of simple modules [2]. Finally, the smaller modules are integrated in one program to solve the complex main problem. The problem could be divided into a set of sub problems which could also be further subdivided into sub sub problems and so on (Figure 5.1). Advanced Topics

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Figure 5.1: The problem decomposition process

For example, if we want to write a program to calculate the standard deviation of a set of numbers. The standard deviation measures the distribution of a set of numbers and how close they are to their average. A standard deviation with low value means the numbers are very close while high values indicate the numbers are dispersed. The standard deviation is calculated using the following equation:

Where :

•

N is the number of numbers (size of the set) that the standard deviation will be calculated for

•

X is the value of each number

•

μ is the mean of the numbers

So if you asked to calculate the standard deviation of (1,2,4,5,7,10), then: •

N = 6 (we have six numbers)

•

Xi takes the values X1=1,X2=2,…X6=10

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To perform the calculation, the program will decompose the main problem into five different sub problems (Figure 5.2). Each one of these problems is calculated alone.

Figure 5.2: Divide the problem into subproblems

Therefore, the problem of calculating the standard deviation of a set of numbers is divided into the following sub problems: •

Count the number of values

•

Calculate the mean of the set of values

•

Calculate the difference and square part

•

Divide the result by N

•

Calculate the square root of the results

•

Output the standard deviation

Hence, the complex problem is transformed into a set of simpler problems that are easy to understand, analyze and then implement.

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5.1.2 Algorithm and Flow Chart Algorithms An Algorithm is a step by step operation of solving a problem. The name of the algorithm comes from "Alkhawarizmi" the Persian Mathematician. In an algorithm, you specify a list of steps for your solution to the problem. For each problem, you may find more than one algorithm to solve the same problem [3]. These algorithms should be evaluated and the one that requires less time and less memory space is selected to be implemented.. The algorithms consists of three parts:

• The inputs: Receive input • The calculation (Processing) in precise steps • The output: Produce output Therefore, the algorithm is a step-by-step set of operations to be performed within a finite amount of space and time. The algorithm starts with an initial state and initial input then executes a computation through a finite number of well-defined successive states to reach the "output". Each mid-state receives an input from its preceding state and produces output to its successor state. The algorithm must be terminated at a final ending state Figure 5.3.

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Figure 5.3: The algorithm steps

If we go back to the previous example of calculating the standard deviation, Figure 5.2 divided the main problem into a set of different smaller problems. Now, the algorithm will arrange the execution of these sub problems. The algorithm will answer the question which problem will be executed first. The algorithm is used to inform the programmers about the sequence of steps for executing the program. Assuming the programmer wrote an algorithm for his/her program as shown in Figure 5.4, the algorithm is divided into three main parts: The input, the processing and the output part. Figure 5.4 shows the algorithm steps for calculating the standard deviation. The figure is divided into the three parts with further calculation of the current example. Advanced Topics

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Figure 5.4: Standard deviation calculation algorithm

The algorithm is proceeding as follows: 1. The input part: a. Read the available input (1,2,4,5,7,10) b. Store the input

2. The processing part a. Count the number of values at the input (N = 6 values) b. Calculate the mean of the input ( = 4.8) c. Calculate the function of the summation of the differences between the value and the mean. d. Divide the results by N e. Calculate the square root of the result

3. The output part: a. 104

Print out to the user the value of the standard deviation.

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Flow Chart A flowchart is a type of diagram that represents an algorithm by showing its steps as boxes of different kinds. The order of these steps is defined by connecting the boxes with arrows. The flow chart gives a solution model to any given problem. Flowcharts are used in understanding, analyzing, designing, or managing a program. The programmer uses the flow chart to understand the required program and start writing their program [4]. The flow chart represents the statements visually using a set of boxes. The boxes are categorized as follows: •

Arrow: Flow line representing the order of the steps inside the algorithm. It starts at one symbol and is directed to another symbol. The arrow shows the flow of information from the start symbol to the end symbol.

•

Terminal: Represented as a circle or oval. It always refers to the start or the end of the algorithm with the word start or end written inside it. Moreover, it may represent the start or the end of any process such as "submit" or "receive fund" .

•

Process: Represented as rectangle. It is used to show that there is a function that should be executed such as "calculate the mean" in the previous example.

•

Decision: represented as diamond. It represents the status where a decision should be made about how the program will proceed. The results are usually be

Figure 5.5: Flowchart symbols

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either yes or no. Two different arrows come out of the decisions; one representing the case if the answer is yes and the other representing when the answer is no. •

Input/Output: Represented as parallelogram. It shows the process of receiving data as input or displaying the final results as outputs.

Figure 5.6 shows the flowchart of the standard deviation example introduced in the previous section

Figure 5.6: Standard deviation flow chart

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5.1.3 Programming languages A programming language is a language designed to communicate instructions to a computer. The programming language is understood by both the programmer who writes the program and the computer that executes it. When the program runs on the computer, the computer performs the functions in the order determined in the program. For each programming language there is a compiler which acts as a translator to translate the code written by the programmer into a behavior for the computers. The programs are used to control different operations by the computer [1]. The programming language consists of: •

Syntax: A combination of different texts including numbers, words and symbols. This combination is called the language code. The syntax should be written in a correct way in order to run and execute the program

•

Compiler: The translator that checks the code of the program and ensures that the syntax of the program is written correctly. The compiler translates the program's instructions into a form that is understood by the computer.

•

Programmer: A human who knows how to write a program using the syntax of the programming language.

As an example, we will give a very short description of the C++ language. C++ is one of the most popular programming languages. This introduction will be divided into three parts: Output, input and processing using C++. Output using C++ The function cout is used to output either text or values to the screen. cout

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The flower picture will appear on the webpage, if not the word Flower picture will appear instead. Images as links Images can be used instead of text as hyperlink. The same tag is used but the image tag is inserted instead of the link text. The HTML tag to use image as hyperlink is as follows:

5.3 Databases An organized collection of data (repository of data). These data are related and organized in a way that ease the process of retrieving required information. Data base is designed in order to: •

Store important information safely: Making paper files for your important information may be lost, destroyed or simply burned. Electronic databases are used to store your important information safely.

•

Retrieve required information easily: When the information is stored safely and in an organised way, the process of retrieving required information from it will be easy.

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Make necessary operations on it: When database is established, you can make extra operation on it such as billing in a supermarket.

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5.3.1 Database Component Database consists of a set of connected relations. Each relation (Entity or Table) consists of a set of attributes (columns). The combinations of these attributes is form a row ( record ) inside the table. For example, Figure 5.14 represent a view of a faculty database. Two table are presented: the doctor table and the students table. The table may called a relation and consists of a set of attributes such as ID, Name, Address and salary in the case of doctors. On the other hand, the student table may collect information about student ID, name, address and class. The information inserted in all these attributes form a row or a record. Each row present a complete information about a certain person in the table. For example, it is clear that there are a doctor that his name is Ahmed and lives in Cairo with id equal ten and with a salary of 5000.

Figure 5.14: A view of a faculty database

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5.3.2 Database people There are a lot of people that may involve in or use the database system. These people are categorized as follows: Database Administrators (DBA) •

Manage the organization resources

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Authorizing access to the database

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Coordinate and monitor the database use

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Decide software/hardware needed

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Design security

Database Designer: •

Deal with the data that should be stored

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Decide the appropriate structure to represent and store the data

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Communicate with end user to understand their requirement

System Analyst: •

Determine the requirement of end user

Programmer: •

Implement the requirement into a program (Develop, debug, test,..)

End user •

Direct use of the database

•

Different types of database users from o Simple user, to o Scientist

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5.3.3 Database Management System (DBMS) A computer software that links the user to the database in order to add or retrieve information to or from the database. The DBMS must be at least capable of performing four main functions: Add, Search, delete and modify. For example, a supermarket database management system main function may be explained as follows: •

Add: The DBMS must be able to add new item to the database. If the super market decide to buy new item that was not found in the database, the DBMS should add it to the established database.

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Search: The DBMS must be able to search inside the database and retrieve any required information. For example, if you want to know the price of a certain item, your DBMS should search for that inside the database and retrieve the price.

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Modify: The DBMS must be able to update information insides the database. For example, if the price of a certain item is increased or decreased, your DBMS should be able to change the price inside the database.

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Delete: The DBMS must be able to delete from the database. For example, if the supermarket decides to stop buying a certain item, your DBMS should delete that item from the database.

Why using DBMS DBMS is used to achieve a set of objectives as follows: 1. Controlling redundancy: 2. In faculty database, a record for each student may be redundantly stored at different departments (accounting, affair, etc..) which wastes effort and storage. Now, we only store each data item in only one place to control the redundancy. 3. Restricting Unauthorized Access Advanced Topics

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4. DBMS is used to organize who can retrieve and update data such as Financial data that should be secrets and limited access. That may be performed by creating accounts and using software or any security methods 5. Providing Backup and Recovery 6. DBMS must have a method to recover from hardware failure. If system fails in the middle of operation, DBMS must restore the system to its valid previous status. 7. Providing Multiple User Interface 8. Provide different interfaces for different users, Interface allow query for programmers users and menu interface for non-specialize users.

5.3.4 Data Model There are three different data models as follows: •

High level(Conceptual data model) : It represents the way that is presented to the end user

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Representational (or implementation) data models : It provides concepts that are easily understood by end users and are not too far from the way data is organized in computer storage.

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Physical data model : Describe the details of how data is stored physically.

5.3.5 Database Architecture The architecture of the database is divided as follows: •

Internal level: This level describes the physical storage structure of database

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Conceptual level: This level describe the structure, Entity, attribute and the relations of the database

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Figure 5.15: Database Architecture

•

The external or view level: includes a number of external schemas or user views. Each external schema describes the part of the database that a particular user group is interested in and hides the rest of the database from that user group.

5.3.6 Database creation using SQL If we have a faculty database and we decide to make two tables: The doctors and the students, then the following steps will be executed: 1. Create the database schema: In this case, we have a database called faculty, then we create the database using the following SQL statement: CREATE SCHEMA FACULTY AUTHORIZATION ‘Ahmed’;

The data base is created and the authorization is given to the user named Ahmed.

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2. Create the first table ( the doctors) and setting up the following conditions: a. The table primary key: One attribute in the table is selected to be the primary key: the attribute that cannot has the same value for two different rows. b. The type and the domain of each attribute: It decide the type of data that are allowed to enter inside the attribute. c. Decide whether that attribute could has a null value or not.

The following SQL statements are used to create a new table: CREATE TABLE DOCTORS ( ID INT Name varchar(50) Address Varchar(5) Salary INT PRIMARY KEY (ID) );

NOT NOT NOT NOT

NULL, NULL, NULL, NULL,

3. By the same way, create the second table. After creating the database and its tables and relations, the four main functions are implemented as follows: 1. Inserting a new value inside the table: To insert a new row inside the table, the following SQL statement is used: INSERT INTO DOCTORS (ID,Name,Address,Salary) VALUES('10','Ahmed','Ismailia','2000')

Note that the order of the data inserted must be the same like the order of the attributes. 2. Search inside the tables: The searching process inside the table may be divided into three different types: a. General search: The results of this search will be the whole table (all rows and all columns). The SQL statement used for the general search is: SELECT * FROM DOCTORS

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b. Semi-general search: The results of this search will be a set of column of the tables not all the columns. The SQL statement used for the semi-genaral search may be: SELECT Name, Address FROM DOCTORS OR SELECT Nam, Address FROM DOCTORS WHERE Salary > 2000

The first statement will return all the rows of the two columns name and address. However, the second statement will return the rows of the two columns of name and address only if they have salary greater than 2000. c. Specific search: The result of this search will be a specific row. This row must satisfy the condition stated at the SQL statement. This condition should be performed over the primary key to be sure that only one row will be returned. he SQL statement used for the the specific search may be: SELECT Nam, Address FROM DOCTORS WHERE ID = 20

3. Update a value in the table: The update statement will replace a value inside the table with a new value. You have to provide a method to search through the table to find the record that you want to update then replace the old value with a new one. The SQL statement that may be used for updating is: UPDATE Doctors SET Name = 'Aly',Address='cairo' WHERE ID = '1'

4. Delete from the table: First a specific row is detected than deleted. The SQL statement that may be used for deleting is: DELETE FROM Doctors WHERE ID = '1'

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5.4 Artificial Intelligence (AI) Artificial intelligence is the process of making the machine behave in intelligent way. Intelligence techniques are used to simulate the human behavior in different situation. For example, simulating the human vision is simply performed by digital camera. However, recognizing and analyzing what is in the picture may need an extra level of intelligence. The main challenge of AI is the robot. The robot should be designed in order to simulate the human behavior [8]. Robot should not only walk, but avoiding the obstacles in front of him also. Robot should not only see, but recognizing what is seen also. These examples and others are considered the main challenges facing artificial intelligence. AI is used to achieve two main goals: •

Create expert system: Expert system is a system that can understand, analyze the problem then provide solutions to the user. The system is trained with different situation and then tested with new situations.

•

Make the machines behave like human: Machines should see, listen, understand and behave like humans using AI.

5.4.1 AI Techniques There are different techniques that are used in AI. The following are a set of the popular AI techniques: •

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Neural Nets: Simulate the behavior of the human neural nets that found in the human brain. The nets consists of different number of layers with a set of neurons in each layer that connected together using a set of weights Figure 5.16. The network is first trained using a set of features with the optimal output as the network target. Then, the network is tested with a new features that never seen before. The network would be able to answer the questions accurately. For example, if you want to train Advanced Topics


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the network to answer the multiplication of 2. Then, the network will trained with a set of multiplication of 2 randomly selected. Therefore, when the network is asked to answer the multiplication of 2 that it didn't seen before, it could estimate the answer based on the trained data.

Figure 5.16: The neural network

•

Classifiers: The machine could be trained to classify. As human can classify the red balls from the black balls easily, the machined may be trained to make the same process. The machine is trained by save the features of different patterns separately. When a new input is processed, the machine compare the input with the saved patterns and the closest match is selected. Decision trees, support vector machine, neural network and others are used as classifiers.

•

Fuzzy rules: A set of if then rules that form a knowledge base that may be used to answer new questions. the knowledge base is built using different rules in different ranges. When a new situation comes, the knowledge base is visited and a new answer is estimated.

5.4.2 AI Applications •

Gaming: AI is used to makes the machine as a second player with the human intelligent. Playing chess with computer is difficult as the computer is trained to detect, understand and beat your play.

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make initial guess of what they suffer. Moreover, the system may advice the doctor with the suitable treatment for the case on hand. •

Natural language processing: Computers are trained to listen and understand the human and then interact with them. The computers can make action using this interaction with no need for the traditional input methods such as mouse or keyboard.

•

Vision systems: Systems that can see and analyze then understand what is seen. For example, criminal system can detect the criminal by recognizing his face.

•

Intelligent robots: Robots that can see and make human duties are available. There are a robot that can play soccer in a way it can see the ball then kick it. These robots are the popular example of AI.

5.5 Exercises 1. What is computer programming? List the steps to generate a complete computer program? 2. The correlation between X and Y measure the degree of dependence between X and Y . it ranges from -1 (negative depending) through 0 (independent) to 1 (identical). The correlation coefficient (r) between X and Y is calculated using the following equation:

3. Using the previous equations, answer the following questions: a. b. c. d. 132

Decompose the problem into subproblems? Write an algorithm to solve the problem? Draw a flow chart of your algorithm? Write a C program to solve the problem?

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4. What is web programming? What are the objects that could be found at a web page? 5. Create a web page that contains: a. b. c. d.

6. 7. 8. 9.

A heading title of your name Your Personal information at the left part of the page Your personal photo at the right part of the page A new page named "Course.html" is opened when your photo is clicked

What is database? why data base is important? What are the component of database? What are the people working at database? Using SQL, create a small database of your courses that includes information about:

a. b. c. d. e. f.

Your name, age, address, cell phone and email Your courses names, class room, hours and grades Your doctors name, age, address, email and salary Insert new information inside the previous tables Delete the doctors that teach database course find the doctors with salary greater than 5000 LE g. Find the name of the students from your country 10. What is Artificial intelligence (AI)? 11. What are the main goals of AI? 12. Describe the main techniques used in AI? 13. List the applications of AI?

5.6 References [1] B. J. MacLennan, Principles of Programming Languages, Oxford University Press, 1987. [2] B. W. Kernighan, The Practice of Programming, Pearson, 1999. [3] R. A. M. (. M. W. E. Grady Booch (Author), B. J. Young, J. Conallen and K. A. Advanced Topics

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Houston, Object-Oriented Analysis and Design with Applications, AddisonWesley Professional, 2007. [4] "SEVOCAB: Software and Systems Engineering Vocabulary Term: Flow chart.," 2008. [Online]. Available: https://pascal.computer.org/sev_display/index.action. [5] S. S. McPherson, Tim Berners-Lee: Inventor of the World Wide Web, TwentyFirst Century Books, 2009. [6] "Web Design or Web Development, What’s The Difference?," purelybranded.com, 2 10 2016. [Online]. Available: http://www.purelybranded.com/insights/web-design-or-web-developmentwhats-the-difference/. [7] "HTML Introduction," w3schools.com, 20 9 2016. [Online]. Available: http://www.w3schools.com/html/html_intro.asp. [8] S. Russell and P. Norvig, Artificial Intelligence: A Modern Approach, Pearson, 2009.

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Chapter 6

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Dr. Mahmoud El-Gayyar

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6 Best Practice This chapter covers a set of essential tutorials required for elementary computer users.

6.1 Microsoft Word Tutorial Microsoft Office 2010 [1] [2] includes programs, servers, and services for individuals and organizations. The insertion point is a blinking vertical line that indicates where text or graphics will be inserted. In Office 2010 programs, the mouse pointer is a symbol that displays on the screen in response to moving the mouse device. A keyboard shortcut is a key or combination of keys that performs a task that would otherwise require a mouse. The Mini toolbar displays commands that are commonly used with the selected object and places common commands close to the pointer. A dialog box is a small window that contains options for completing a task. Whenever a command is followed by an ellipsis (…), clicking the command always displays a dialog box. A gallery is an Office feature that displays a list of potential options such as color, fill options, and so on. A ScreenTip displays useful information about mouse actions, such as pointing to screen elements or dragging.

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A location is any disk drive, folder, or other place in which files and folders can be stored. Microsoft Office Backstage view is a centralized space for tasks related to file management. The Backstage tabs are: •

Info

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Recent

•

New

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Print

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Save & Send

•

Help

Document properties, also known as metadata, are details about a file that describe or identify it, such as the title, author name, subject, and keywords that identify the document's topic or contents. The process of printing a file is similar in all of the Office applications. However, there are differences in the types of options you can select. For example, in PowerPoint, you have the option of printing: •

The full slide, with each slide printing on a full sheet of paper.

•

Handouts with small pictures of slides on a page.

Print Preview displays a view of a document as it will appear on the paper when it is printed. At the bottom of the Print Preview area, on the left, the number of pages and arrows are used to move among the pages in Print Preview display. [3] In Office 2010, some files open in Protected View if the file appears to be from a potentially risky location, such as the Internet. Protected View is a new security Best Practice

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feature in Office 2010 that protects a computer from malicious files by opening them in a restricted environment until they are enabled. Characters created by pressing the Enter, Space, or Tab keys do not print, and are referred to as formatting marks or nonprinting characters. The Ribbon, which displays across the top of the program window, groups commands and features in a way that they are most logically used. Each Office program's Ribbon is slightly different, but all contain the same three elements: •

Tabs display across the top of the Ribbon, and each tab relates to a type of activity.

•

Groups are sets of related commands for specific tasks.

•

Commands—instructions to computer programs—are arranged in groups and are displayed as a button, a menu, or a box in which information is typed.

The Quick Access Toolbar contains commands that you use frequently. By default, only the commands Save, Undo, and Redo display, but commands can be added and deleted as desired.

Figure 6.1: Quick Access Toolbar

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Images can be inserted in to a document by clicking the Clip Art button. When doing so, the Clip Art task pane is displayed. A task pane is a window within a Microsoft Office application that enables options to be entered to complete a command. Formatting is the process of establishing the overall appearance of text, graphics, and pages in an Office file.

Figure 6.2: Formatting

Headers and footers can be added to a document. A footer is a reserved area for text or graphics that displays at the bottom of each page in a document. Likewise, a header is a reserved area for text or graphics that displays at the top of each page in a document. A document can be displayed in portrait or landscape orientation. In portrait orientation, the paper is taller than it is wide. In landscape orientation, the paper is wider than it is tall. Best Practice

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A font is a set of characters with the same design and shape. The default font in a Word document is Calibri, which is a sans serif font—a font design with no lines or extensions on the ends of characters. The Cambria font is a serif font—a font design that includes small line extensions on the ends of the letters to guide the eye in reading from left to right. A theme is a predesigned set of colors, fonts, lines, and fill effects that look good together and that can be applied to an entire document or to specific items. A theme combines two sets of fonts—one for text and one for headings. Font styles include bold, italic, and underline. Font styles emphasize text and are a visual cue to draw the reader's eye to important text. The Format Painter is used to copy the formatting of specific text or of a paragraph and then apply it in other locations in a document. The Office Clipboard is a temporary storage area that holds text or graphics that were selected and then cut or copied. When text or graphics are copied, a copy is placed on the Office Clipboard and the original text or graphic remains in place. When text or graphics are cut, a copy is placed on the Office Clipboard, and the original text or graphic is removed—cut—from the document. After cutting or copying, the contents of the Office Clipboard are available to paste—inserting—in a new location in the current document, or into another Office file.

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To add visual interest to a document, graphics can be inserted. Graphics include pictures, clip art, charts, and drawing objects—shapes, diagrams, lines, and so on. Additionally, text can be converted to an attractive graphic format; pictures can be added, resized, moved, and formatted, and a page border can be added. Word inserts the picture as an inline object; that is, the picture is positioned directly in the text at the insertion point, just like a character in a sentence. An inline object can be changed to a floating object—a graphic that can be moved independently of the surrounding text characters. Text wrapping refers to the manner in which text displays around an object. Picture styles include shapes, shadows, frames, borders, and other special effects with which you can stylize an image. Artistic effects are formats that make pictures look more like sketches or paintings. Word provides predefined shapes and text boxes that can be added to a document. •

A shape is an object such as a line, arrow, box, callout, or banner.

•

A text box is a movable, resizable container for text or graphics.

As with graphics, shapes and text boxes can be moved, resized, and formatted. Information in headers and footers helps to identify a document when it is printed or displayed electronically.

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When the body of the document is active, the footer text is dimmed—displays in gray. Conversely, when the footer area is active, the footer text is not dimmed; instead, the document text is dimmed. Document layout includes margins—the space between the text and the top, bottom, left, and right edges of the paper.

Figure 6.3: Setting Margins

Paragraph layout includes line spacing, indents, and tabs. Alignment refers to the placement of paragraph text relative to the left and right margins. Line spacing is the distance between lines of text in a paragraph. Lists of information can be highlighted by using bullets or numbers. •

A bulleted list uses bullets—text symbols such as small circles or check marks—to introduce each item in a list

•

A numbered list uses consecutive numbers or letters to introduce each item in a list.

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By default, Word formats bulleted items with a first line indent of .25 inch and adds a Hanging Indent at .5 inch. The hanging indent maintains the alignment of text when a bulleted item is more than one line. When creating a numbered list, Word uses predictive logic to determine that this paragraph is the first item in a numbered list and formats the new paragraph accordingly, indenting the list in the same manner as the bulleted list. The space after the number changes to a tab. Tab stops mark specific locations on a line of text. Tab stops are used to indent and align text, and the Tab key is used to move to tab stops. SmartArt graphics are designer-quality visual representations of information, and Word provides many different layouts from which you can choose.

Figure 6.4: Insert Smart Art

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6.2 Microsoft Excel Tutorial A workbook—an Excel document that stores data—contains one or more pages called a worksheet. A worksheet—or spreadsheet—is stored in a workbook, and is formatted as a pattern of uniformly spaced horizontal rows and vertical columns. The intersection of a column and a row forms a box referred to as a cell. [4] Cell content is anything typed in a cell and can be one of two things: either a constant value—referred to simply as a value—or a formula. A formula is an equation that performs mathematical calculations on values in a worksheet. The most commonly used values are text values and number values, but a value can also include a date or a time of day.

Figure 6.5: Excel Main Screen

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A text value, also referred to as a label, can provide information about number values in other worksheet cells. A label is usually an example of a field heading, thus it is descriptive of values in the column or row cells that follow. The intersecting column letter and row number form the cell reference or cell address. Text or numbers in a cell are referred to as data. If the first few alphabetic characters typed in a cell match an existing entry in the column, Excel uses AutoComplete to fill in the remaining characters. Auto Fill generates and extends a series of values into adjacent cells based on the value of other cells. By dragging the fill handle—the small black square in the lower-right corner of a selected cell—to adjacent cells, the cells are filled with values based on the first cell.

Figure 6.6: Auto Fill

Some Excel defaults are: • • • • • • •

Column width is 64 pixels Font is Calibri Font size is 11 pt Number values are aligned at the right edge of the cell Number format is the general format The displayed value is shown for data in a cell The underlying value is shown for data in the Formula Bar Best Practice

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A cell can contain either a constant value (text or numbers) or a formula. A formula is an equation that begins with the equal sign (=) and performs mathematical calculations on values in other cells and places the result in the cell containing the formula. A function is a prewritten formula that looks at one or more values, performs an operation, and returns a value. An example of a function used in this objective is SUM, which sums a group of numbers. Since SUM is a frequently used function, it can be implemented by using the AutoSum button. There are four ways to create a formula: • • • •

By typing By using the point-and-click technique By using a function button from the Ribbon By copying a formula from one cell to another

You can specify a range of cells as an input for a function that are two or more cells that are adjacent or nonadjacent. A range colon (:) appearing between two cell references includes all cells between the two cell references. For example: B3:D3 is a range that includes cells B3, C3, and D3. When copying a formula, Excel copies the formula but adjusts the cell references relative to the row number. This is called a relative cell reference—a cell reference based on the relative position of the cell that contains the formula and the cells referred to.

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Figure 6.7: Use the Sum Function

To Format—refers to changing the appearance of cells to make a worksheet attractive and easier to read. The Merge & Center command joins a selected range of cells into one larger cell and centers the contents in the new cell. Individual cells in the range can no longer be selected. A cell style is a defined set of formatting characteristics, such as font, font size, font color, cell borders, and cell shading. Two styles used for formatting financial numbers are: •

•

The Accounting Number Format applies a thousand comma separator where appropriate, inserts a fixed dollar sign ($) aligned at the left edge of the cell, applies two decimal places, and leaves a small amount of space at the right edge of the cell to accommodate a parenthesis when negative numbers are present. The Comma Style inserts thousand comma separators where appropriate and applies two decimal places. Comma Style also leaves space at the right to accommodate a parenthesis when negative numbers are present.

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Figure 6.8: Format Worksheet

When preparing worksheets with financial information, the first row of dollar amounts and the total row of dollar amounts are formatted in the Accounting Number Format. Rows that are not the first row or the total row should be formatted with the Comma Style. A chart is a graphic representation of data in a worksheet. Data presented as a chart is easier to understand than a table of numbers.

Figure 6.9: Excel Charts

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Sparklines are tiny charts embedded in a cell and give a visual trend summary alongside your data; a sparkline makes a pattern more obvious to the eye.

Figure 6.10: Excel Sparklines

Some of the components of a column chart are: • • • • •

Category labels—the labels that display along the bottom of the chart to identify the category of data. Category axis or the x-axis—Excel uses the row titles as the category names and displays them below the horizontal axis. Value axis or y-axis—Excel includes a numerical scale on the left on which the charted data is based. Legend— identifies the patterns or colors on the right that are assigned to the categories in the chart. Data point—a value that originates in a worksheet cell and each data point is represented in the chart by a data marker—a column, bar, area, dot, pie slice, or other symbol in a chart that represents a single data point. The related data points form a data series.

The Chart Styles gallery displays an array of pre-defined chart styles—the overall visual look of the chart in terms of its colors, backgrounds, and graphic effects. Page Layout view is used to view and prepare a workbook for printing.

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In Page Layout: • • • •

Footers can be inserted Margins can be modified Pages can be aligned Information such as the author, subject, and keywords can be added

Normal view maximizes the number of cells visible on the screen and keeps the column letters and row numbers closer. The vertical dotted line between columns indicates that, as currently arranged, only the columns to the left of the dotted line will print on the first page. The Show Formulas button can be used to display the underlying formulas instead of the results of the formulas. In Excel, the spelling checker performs similarly to the other Microsoft Office programs. The Spelling command begins its checking process with the currently selected cell and moves to the right and down. If the spelling tool does not have this word in its dictionary, then under Suggestions, Excel provides a list of suggested spellings. Text that is too long to fit in a cell spills over to cells on the right only if they are empty. If the cell to the right contains data, the text in the cell to the left is truncated. However, the entire text value is displayed in the Formula Bar. Data can be entered by first selecting a range of cells, and this can be a timesaving technique, especially when using the numeric keypad to enter the numbers. Remember the default number format for cells is the General number format, in which numbers display exactly as they are typed and trailing zeros do not display, even if they were typed. 150

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Operators are symbols that specify the type of calculation to be performed in a formula.

Figure 6.11: Arithmetic Operators

We already discussed that a relative cell reference refers to a cell by its position in relation to the cell that contains the formula and is automatically adjusted when a formula is copied. On the other hand, an absolute cell reference refers to a cell by its fixed position in the worksheet. A dollar sign ($) prefixed to a column letter or row number indicates an absolute reference to that column or row.

Figure 6.12: Absolute Cell

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One of the most powerful and valuable features of Excel is when changes are made to a cell, Excel automatically re-calculates any formulas that reference that cell. You can edit text and number values directly within a cell or on the Formula Bar. The Percent Style button can be used to format selected cells as a percentage rounded to the nearest hundredth. Formatting refers to the process of specifying the appearance of cells and the overall layout of a worksheet. Formatting is accomplished: • • • •

Through various commands on the Ribbon From shortcut menus By keyboard shortcuts By using the Format Cells dialog box

The Wrap Text command can be used to display the contents of a cell on multiple lines. The Middle Align command is used to align text so that it is centered between the top and bottom of the cell. The orientation of a page—portrait or landscape—can be changed. Statistical functions, such as AVERAGE, MEDIAN, MIN, and MAX functions, are useful to analyze a group of measurements.

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Figure 6.13: Statistical functions

When using functions, the values in parentheses are the arguments—the values that an Excel function uses to perform calculations or operations. The AVERAGE function adds a group of values, and then divides the result by the number of values in the group. The MEDIAN function finds the middle value that has as many values above it in the group as are below it. The MIN function determines the smallest value in a selected range of values. The MAX function determines the largest value in a selected range of values. When a formula is moved, the cell references within the formula do not change, no matter what type of cell reference is used. If cells are moved into a column that is not wide enough to display number values, Excel will display a message so that any necessary adjustments can be made. Data can be repositioned within a cell at an angle by rotating the text. Rotated text is useful to draw attention to data on a worksheet.

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If a cell width is too narrow to display an entire number, Excel displays the ##### error, because displaying only a portion of a number would be misleading. The underlying values remain unchanged and are displayed in the Formula Bar. Excel functions include logical functions, which test for specific conditions. Logical functions typically use conditional tests to determine whether specified conditions—called criteria—are true or false. The COUNTIF function is a statistical function that counts the number of cells within a range that meet the given condition—the criteria that is provided. The COUNTIF function has two arguments—the range of cells to check and the criteria. A logical test is any value or expression that you can evaluate as being true or false, and the IF function uses a logical test to check whether a condition is met, and then returns one value if true, and another value if false. Comparison operators are used to compare values in a logical test.

Figure 6.14: The Logical If Function

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A conditional format changes the appearance of a cell based on a condition—a criteria. If the condition is true, the cell is formatted based on that condition; if the condition is false, the cell is not formatted.

Figure 6.15: Conditional Formatting

A data bar provides a visual cue to the reader about the value of a cell relative to other cells. The length of the data bar represents the value in the cell. A longer bar represents a higher value and a shorter bar represents a lower value. Data bars are useful for identifying higher and lower numbers quickly within a large group of data, such as very high or very low levels of inventory. The Find and Replace feature searches the cells in a worksheet—or in a selected range—for matches, and then replaces each match with the replacement value of your choice. Excel can obtain the date and time from a computer’s calendar and clock, and display this information on a worksheet. By freezing or splitting panes, you can view two areas of a worksheet or lock rows and columns in one area. When freezing panes, the specific rows or columns are selected, and they remain visible when scrolling in the worksheet. Best Practice

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The NOW function retrieves the date and time from a computer’s calendar and clock, and inserts the information into the selected cell. The result is formatted as a date and time. The NOW function is volatile, which means the date and time will not remain as entered, but rather the date and time will automatically update each time the workbook is opened. A pane is a portion of a worksheet window bounded by and separated from other portions by vertical or horizontal bars, and the Freeze Panes command is used to select one or more rows or columns and then freeze (lock) them into place. To analyze a group of related data, a range of cells can be converted into an Excel table. An Excel table is a series of rows and columns that contains related data that is managed independently from the data in other rows and columns in the worksheet. Once an Excel table has been created, one can: • •

Sort the table—arrange all the data in a specific order—in ascending or descending order. Filter the table—display only a portion of the data based on matching a specific value—to show only the data that meets the specified criteria.

After any sorting, filtering, and totaling have been performed, the table can be converted back into a normal range. Converting to a normal range can also be useful if the only table feature you want to apply is an attractive Table Style to a range of cells.

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If a worksheet is too wide, too long—or both—to print on a single page, Excel’s Print Titles and Scale to Fit commands can be used to create pages that are attractive and easy to read. The Print Titles command is used to specify rows and columns to repeat on each printed page. The Scale to Fit command is used to stretch or shrink the width, height, or both, of printed output to fit a maximum number of pages.

Figure 6.16: Scaling Worksheets while Printing

Multiple worksheets are used in a workbook to organize data in a logical arrangement. When there is more than one worksheet in a workbook, click the sheet tabs to navigate among worksheets. Sheet tabs identify each worksheet in a workbook and are located along the lower left edge of the workbook window. Best Practice

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Excel names the first worksheet in a workbook Sheet1 and each additional worksheet in order—Sheet2, Sheet3, and so on. Most Excel users rename the worksheets with meaningful names. Dates represent a type of value that is entered in a cell. When a date is entered, Excel assigns a serial value—a number—to the date. This makes it possible to treat dates like other numbers, so finding the number of days between the two dates is done by subtracting the older date from the more recent date. A cell has contents—a value or a formula—and a cell may also have one or more formats applied. One can clear—delete—the contents of a cell, the formatting of a cell, or both. • •

Clearing the contents of a cell deletes the value or formula typed there, but it does not clear formatting applied to a cell. Clearing the formats deletes formatting from the cell, but does not delete the cell’s contents.

Data in cells can be copied to other cells in the same worksheet, to other sheets in the same workbook, or to sheets in another workbook. The action of placing cell contents that have been copied or moved to the Office Clipboard into another location is called paste. When pasting, the Paste Options gallery is displayed. Live Preview is also displayed and shows how the copied cells will look when placed in the worksheet. When pasting a range of cells, one only needs to point to or select the cell in the upper left corner of the paste area—the target destination for data that has been cut or copied using the Office Clipboard.

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Data can be entered or edited on several worksheets at the same time by selecting and grouping multiple worksheets. Data that is entered or edited on the active sheet is reflected in all selected sheets. When worksheets are grouped, [Group] displays in the title bar, and the sheet tabs are underlined in the tab color to indicate they are selected as part of the group. A summary sheet is a worksheet where totals from other worksheets are displayed and summarized.

Figure 6.17: Summary Sheet

A Summary worksheet accurately displays the current totals from the other worksheets, which are sometimes referred to as detail sheets. Remember sparklines are tiny charts within a single cell that show a data trend. Each worksheet within a workbook can have different formatting. However, if the same formatting is desired, all the worksheets can be selected and common formatting can be applied to all of the worksheets. To print all worksheets, group them and, in the Print group, click the Print button. Best Practice

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6.3 Microsoft PowerPoint Tutorial Microsoft PowerPoint 2010 [5] is software that can be used to effectively present information to an audience. Before speaking about the details of the PowerPoint program, we would like to focus on a set of hints to make effective PowerPoint presentations: 1. Eye contact: Throughout your presentation you must have an eye contact with every person so that you could deliver your message persuasively to everyone. 2. Be Entertaining: To grab audience attention, your speech should be informative and interesting, so instead of reciting dry facts try to add humor in your presentation. But, try not to be funny at serious matters. 3. 10-20-30 Rule for slideshow: It means your presentation should not exceed 10 slides and duration more than 20 minutes also not less than 30 point font. These collectively make your presentation effective. 4. Slow down: Generally, due to nervousness people try to complete their speech in rush. So, it is advisable to consciously control your speed and give appropriate pauses. 5. 15 words summary: Filter 15 key words of your presentation and repeat these to communicate your message well. 6. Don’t read: Avoid reading slides while giving presentation as it can distract audience attention from your speech. 7. Project your voice: You must be clearly audible to everyone, for this you need to project your voice. Yes, pitch of your voice should possess required variations and pauses. 160

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8. Speeches are about stories: If your presentation is going to exceed try cover up points by correlating it with stories. Moreover, speaker should have this art of creating stories instantly. 9. Appreciate queries: Instead of creating sounds like umm… ah… and all that while handling query, try to appreciate all query by using phrases like ‘very good question’ , ‘thank you for query’ all these can give you a moment to gather the answer for the asked question and viewers will never come to know about your trick!! 10. Reach venue before time: Setting projector and other preparations are not accepted when people are waiting for you to speak. So, it important to reach venue before time and make required alterations and this can curb your anxiety to a great extent. 11. Practice Practice Practice: Practicing in front of mirror or audience can make you a strong competent and will also boost up your confidence. 12. Don’t apologize unnecessarily: It is not advisable to apologize for the things like, for getting nervous while delivering speech, for lacking in preparation or for getting anxious, it looks awkward. 13. Apologize where required: Only Apologize if you have reached late or you have made any considerable mistake, otherwise it is not required for being humble. 14. Have fun: Practice to inject passion and enthusiasm in your presentation to make it interesting and lively

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Coming back to the PowerPoint program, The following objects are parts of the its window: • • • • •

Notes pane Slide pane Slides/Outline pane Status bar View buttons

Figure 6.18: Normal View in PowerPoint

A placeholder is a box on a slide with dotted or dashed borders that holds title and body text or other content such as charts, tables, and pictures. A theme is a set of unified design elements that provides a look for your presentation by applying colors, fonts, and effects.

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Figure 6.19: PowerPoint Theme

Editing is the process of modifying a presentation by adding and deleting slides or by changing the contents of individual slides. Text in a PowerPoint presentation is organized according to list levels. List levels, each represented by a bullet symbol, are similar to outline levels. On a slide, list levels are identified by the bullet style, indentation, and the size of the text. The first level on an individual slide is the title. Increasing the list level of a bullet point increases its indent and results in a smaller text size. Decreasing the list level of a bullet point decreases its indent and results in a larger text size. The AutoFit Text to Placeholder option keeps the text contained within the placeholder by reducing the size of the text. The Stop Fitting Text to This

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Placeholder option turns off the AutoFit option so that the text can flow beyond the placeholder border with the text size remaining unchanged. Photographic images add impact to a presentation and can help the audience visualize the messages the presenter is trying to convey. When a picture is clicked, small circles and squares—sizing handles—surround the inserted picture and indicate that the picture can be modified or formatted. The rotation handle—a green circle above the picture—provides a way to rotate a selected image.

Figure 6.20: Add Picture to a Presentation

When a presentation is viewed as an electronic slide show, the entire slide fills the computer screen, and an audience can view the presentation if the computer is connected to a projection system. Prior to printing, the Backstage view can be used to preview the arrangement of slides on the handouts and notes pages. 164

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Figure 6.21: Printing a Presentation

Presentation content can be edited in either the Slide pane or in the Slides/Outline pane. Displaying the Outline tab allows the entire flow of the presentation to be viewed. Formatting refers to changing the appearance of the text, layout, and design of a slide, and it is easiest to do most of the formatting changes to a slide in the Slide pane. Slide Sorter view displays thumbnails of all of the slides in a presentation. To move a slide to a new position, hold down the left mouse button, drag the thumbnail of the slide to where the slide will be repositioned, and when a vertical move bar appears, release the button.

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Figure 6.22: Slide Sorter

Slide transitions are the motion effects that occur in Slide Show view when moving from one slide to the next during a presentation. The Transitions gallery categorizes transitions into Subtle, Exciting, and Dynamic Content. The Effect Options vary depending upon the selected transition and include the direction from which the slide enters the screen or the shape in which the slide displays during the transition. The Timing group is used to determine the duration of the transition, if the presenter controls the method used for the advancement to the next slide, and to control if the transition is applied to all slides.

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Figure 6.23: Slide Transitions

The format of a slide’s content can be modified by changing its bulleted and numbered list styles and colors. When formatting the contents of a placeholder, changes can be made to selected text or to the entire placeholder. A bulleted list can be changed to a numbered list. All of the bullet symbols are converted to numbers, and the color of the numbers is determined by the presentation theme. One of the sources for presentation images is a clip—a single media file such as art, sound, animation, or a movie. Microsoft Office includes a gallery of clip art files. The gallery can include online clips from Office.com. Once placed on a slide, the images can be formatted as desired. Best Practice

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Figure 6.24: Insert a Clip Art

The Crop button is a split button that can crop—reduce the viewable area size of an image or make an image conform to a shape. A text box is an object with which you can position text anywhere on a slide, and is used to draw attention to important information or serve as a container for slide text. Shapes include lines, arrows, stars, banners, ovals, rectangles, and other basic shapes used to illustrate an idea, a process, or a workflow. Changing the inside fill color and the outside line color is a distinctive way to format a shape. A fill color is the inside color of text or of an object. Combinations of shape fill, outline colors, and weights can be used to format an object. When more than one instance of an object is desired, Ctrl + D will make duplicate copies of it. Selected objects can be aligned and distributed on a slide. 168

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Background Removal can be used to avoid the boxy look of an inserted image. It flows a picture into the content of the presentation and removes unwanted portions of a picture so that the picture does not appear as a self-contained rectangle.

Figure 6.25: Background Removal

WordArt is a gallery of text styles that can be used to create decorative effects, such as shadowed or mirrored. Existing text can be modified by applying WordArt formatting. A SmartArt graphic is an effective visual representation of information that is created by selecting from a variety of layouts. SmartArt Styles are combinations of formatting effects that can be applied to SmartArt graphics.

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Figure 6.26: Smart Art

6.4 Exercises Choose the right Answer from the following: 1. Details about a file, including the title, author name, subject, and keywords are known as: A. document properties B. formatting marks 2. An Office feature that displays a list of potential results is:

C. KeyTips

A. Live Preview B. a contextual tab C. a gallery 3. A type of formatting emphasis applied to text such as bold, italic, and underline, is called a: A. font style B. KeyTip C. tag 4. A technology showing the result of applying formatting as you point to possible results is called: A. Live Preview B. Backstage view C. gallery view 5. A temporary storage area that holds text or graphics that you select and then cut or copy is the: A. Paste Options gallery Clipboard

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6. Characters that display on the screen to show the location of paragraphs, tabs, and spaces, but that do not print, are called: A. text effects B. bullets C. formatting marks 7. An object or graphic inserted in a document that acts like a character in a sentence is a(n): A. floating object B. inline object C. text box 8. A commonly used alignment of text in which text is aligned at the left margin, leaving the right margin uneven is called: A. left alignment B. justified alignment C. right alignment 9. The spaces between the text and the top, bottom, left, and right edges of the paper are referred to as: A. alignment 10. Tab stops are a form of:

B. margins

A. line formatting B. document formatting formatting 11. On startup, Excel displays a new blank:

C. spacing C. paragraph

A. record B. workbook C. grid 12. An Excel window element that displays the value or formula contained in the active cell is the: A. Name Box B. status bar C. Formula Bar 13. The feature that generates and extends values into adjacent cells based on the values of selected cells is: A. AutoComplete B. Auto Fill C. fill handle 14. The type of cell reference that refers to cells by their fixed position in a worksheet is: A. absolute B. relative C. exponentiation 15. Tiny charts embedded in cells that give a visual trend summary alongside your data are: A. embedded charts B. sparklines C. chart styles 16. The function that retrieves and then displays the date and time from your computer is the: A. DATE function B. NOW function 17. A function that determines the largest value in a range is the: A. MEDIAN function

B. MAX function

C. CALENDAR function C. MIN function

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18. The command that enables you to select one or more rows or columns and lock them into place is: A. Drag and Drop B. Scale to Fit C. Freeze Panes 19. A series of rows and columns with related data that is managed independently from other data is a: A. table B. pane C. detail sheet 20. The process of arranging data in a specific order based on the value in each field is called: A. filtering B. sorting C. scaling 21. The arrangement of elements, such as title and subtitle text, lists, pictures, tables, charts, shapes, and movies, on a PowerPoint slide is referred to as: A. theme modification B. editing C. layout 22. Text that prints at the top of a sheet of slide handouts or notes pages is a: A. header B. footer C. page number 23. Text that displays at the bottom of every slide or that prints at the bottom of a sheet of slide handouts or notes pages is the: A. header B. footer C. page number 24. The command that locates all occurrences of specific text and substitutes it with alternative text is: A. Replace B. Find C. Edit 25. The view in which all of the slides in your presentation display as miniature images is: A. Slide Sorter view

B. Normal view

C. Reading view

26. A view similar to Slide Show view but that also displays the title bar, status bar, and taskbar is: A. Slide Sorter view B. Normal view C. Reading view 27. A printout that contains the slide image on the top half of the page and notes that you have created in the Notes pane on the lower half of the page is a: A. handout B. notes page C. slide 28. The command that removes unwanted portions of a picture so that the picture does not appear as a self-contained rectangle is: A. Shape Height

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6.5 References [1] S. Gaskin, N. Graviett and D. Geoghan, Go! All in One: Computer Concepts and Applications, 2nd ed., Upper Saddle River, NJ, USA: Prentice Hall Press, 2014. [2] Microsoft, "Microsoft Office," [Online]. Available: https://support.office.com/. [Accessed September 2016]. [3] D. Gookin, Word 2016 For Dummies, Wiley, 2015. [4] G. Harvey, Excel 2013 All-in-One For Dummies, Wiley, 2013. [5] D. Lowe, PowerPoint 2013 For Dummies, Wiley, 2013.

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