COMPUTER Project - SEE, NEB , Engineering Notes - WordPress.com

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This computer project is a result of my experience, knowledge, dedication, consultation with computer science experts and teachers, and references to quality books and websites I have tried my best to include the quality content, and avoid all kinds of errors as far as possible. At last, I would like to remember and thank every individual who helped me to complete my project report successfully. Love you all! I am also graceful to my parents for their inspirations, cooperation, and support.

Name: Grade : Section: Date:GRADE XI FROM: Shift : Science Stream DATE: 2070/01/08 -0-

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1. INTRODUCTION AND EVOLUTION OF COMPUTER: A computer is a general purpose device that can be programmed to carry out a finite set of arithmetic or logical operations. Since a sequence of operations can be readily changed, the computer can solve more than one kind of problem .A computer independent of its size, is an electronic device used for processing of data and text. Computer is one of the greatest inventions of human mind. Computer has strengthened our capacity in numerical computations, information processing, storage, modelling and simulations. Computer is, in fact, a dumb machine in the absence of human intervention. That means Computer cannot do anything in its own, user must provide appropriate instructions to the computer to generate useful result.

Computer has become an indispensable machine to increase the effectiveness and efficiency of every person, organization, country, student, teachers, scientist, researchers and of every field including education, business, industry, science, technology, astrology, mining and many more. It has become a basic need of most of the people just like television, telephone and other electronic devices at home and gaining popularity among others as well. It can solve numerical, logical or other decision related human problems very quickly as well as accurately. The most important features of the computer are: 1.1) Speed: Computer is very high speed electronic device. The operations on the data inside the computer are performed through electronic circuits according to the given instructions. The data and instructions flow along these circuits with high speed that is close to the speed of light. Computer can perform millions of billions of operations within a second. Speed of computer performance is measured in Megahertz (MHz) or in Gigahertz (GHz).Different computers have different speed. 1.2) Accuracy: Computer is very fast and accurate device. It gives accurate output result provided that the correct input data and set of instructions are given to the computer. It means the output is totally dependent on the given instructions and input data. If input data is incorrect then the output is also incorrect. In computer terminology it is known as Garbage In Garbage Out (GIGO). 1.3) Storage: The computer has internal storage as well as external or secondary memory (storage).In secondary storage, a large amount of data and programs can be stored for future use. The stored data and programs are available any time for processing. Similarly, the information downloaded from the internet can be stored on the storage media. 1.4) Automation: A computer can automatically perform operations without interfering to or the intervention of the user during the operation. It controls automatically different devices attached with the computer. It executes automatically the program instructions one by one. COMPUTER Project

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1.5) Reliability: The electronic components in modern computer has very low rate of failure. The modern computer can perform very complicated calculations without creating any problem and produces reliable results. In general, computers are very reliable. Communications are also very reliable and generally available whenever needed. 1.6) Diligence: A computer can continually work for many hours without creating any errors. It does not get tired while working for many hours. It performs the operations with the same accuracy, reliability as well as speed as in initial. 1.7) No feelings: Computer is an electronic device. It has no feelings. It detect object on the basis of instructions given to it.Based on our feelings, taste, knowledge and experience, we can make certain decisions and judgements. On the other hand, computers cannot make such decisions and judgements on their own. Their judgements are totally based on instructions given to them. 1.8) Versatility: Versatile means flexible. Modern computer can perform different kind of tasks one by one or simultaneously. It is the most important feature of computer. The talent of the computer is dependent on the software. Computer can be used in every field like science, technology, automation, education, medicinegovernance etc. 1.9) Precision: Computers are not only fast and consistent but they also perform operations very accurately and precisely. In computer however, you can keep the accuracy and precision up to the desired level. The length of calculations or decimal places always remains accurate. 2. Application of Computer: Computer is playing very important role in every field of life. Computers are every-where such as at home, at school, at working place, at entertainment etc. In daily life a large number of activities are dependent on computers. The main fields where computer is playing very important role are: 2.1) Education: Education is the process of developing knowledge through instructions. The instructions are received from people such as parents, teachers etc. and from printed material such as book, journals etc. Today, the modern technique to get knowledge is by using computers. All schools use computers in classroom and labs to teach students. Many educators prefer to deliver their lectures by computer-based presentations or multimedia programs. In school, colleges & universities, students use software packages to complete their assignments. The computer assisted learning (CAL), Computer-based training (CBT) or presentation is also called computer aided instructions (CAI).In this method, computer is used as an aid to teach the student in the classroom. The web-based training (WBT) is another type of CBT that uses internet technology. It means that many websites provide online education. A lot of materials on different topics are available on these websites. They also provide online lectures and tutorials for the students. The CBT & WBT are used in business education centres to educate people. People can get knowledge at very low cost as well as in very short period of time. Most of the WBT are free of cost. 2.2) Entertainment: Computer has played a very important role in entertainment for different levels of people. Computer has become need of human for entertainment at their home, like playing video games. Similarly, COMPUTER Project

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software is available to see movies and to listened music. Today, the movie files and famous songs are mostly available on CDs or on the web at very low cost. We can listen while work on the computer. On the web, we can view fine art images in online museums and galleries. Some artists sell their works online and others display them for our viewing pleasure. 2.3) Science and Engineering: Computer is in all branches of science and engineering to collect and analyse data. The scientists also use internet to collect the latest information around the world .Today, it is impossible to carry out scientific researches without use of computer. In all branches of science, it is mainly used to get accurate experimental results, for example to get accurate forecasting of weather etc. 2.4) Publishing: In the field of publishing, Computer is playing very important role to publish the books, magazines and newspaper etc. The publishers use computer and word processor and graphic software to design pages of the books or magazines. Many writers and publishers use internet to collect information that is used for compiling a new book of magazine. Some websites allow you to download an entire book, called an electronic book (e-book).The journalist also use notebook computers and digital computers to capture and record news. 2.5) Home: Like other electronic devices used in home such as TV, Washing machine etc. Computer has also become the need of every person at home. It is used at home as an educational tool for children. But it is also used at home to keep records, write letters, prepare budgets, connect with others to get information on the internet, to watch films and to listen music or other entertainment etc. 2.6) Agriculture: In agriculture field also, computer is playing very important role. The agricultural scientists are using computer for analysing the agricultural data. The students of agriculture also uses computer to get latest information about agriculture on the internet. The farmers also use computer to get information about crops to calculate bills and cost price per acre, advertise their products and to get information about crops market prices. 2.7) Energy: Energies company use computers to locate or search oil, coal, natural gases and uranium. Similarly electric power companies use computer to monitor the power networks. Meter readers use hand held computers to record the units consumed in homes and business. 3. History of Computer: The development of computer was not spontaneous. Many scientists and many activities contributed to the history of computers. Computer is a complex machine having many components interrelated with each other. Each of these components was invented separately and by different inventors. Therefore, in terms of technological innovations, method of operation, and the historical perspective of phases of computer development, the historical time period can be divided into three different eras:

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First era: Pre-history era or pre-mechanical era(500BC-1642) Second era: Mechanical era (1642-1890) Third era: Electro-mechanical era (1890-1945) Fourth era: Electronic era (1946- today)

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3.1 First era: Pre-history era or pre-mechanical era (500BC-1642): This was the period between 500 BC to 1642 A.D.During The earlier days of prehistory, simple tools were used for calculations. Abacus was the most significant and earliest computing tool that marked the existence of modern computers. The Abacus is considered as first personal calculator. The details of different devices invented during this era are given below: 3.1.1. Abacus: The Abacus is the earliest and the simplest calculating device. The Abacus is also known as “soraban”.It was developed and used in China in 500BC.The Abacus was a very simple computing device used for simple addition and subtraction. It consists of a rectangular wooden frame having parallel wires. Each wire supports a number of beads.The bead across the wires is free to move along the lengths of wire. Each bead down represents a digit. The position of wires and their values are: o The beads in the first wire on right represent the unit digit. o The beads in the second wire on right represent the tens digit. o The beads in the third wire on right represent the hundreds digit and so on.

3.1.2Calculating device of John Napier: In the early 17th century, the famous logarithms idea was developed by John Napier, a Scottish Mathematician. He created logarithms table for arithmetic calculations. He also developed a new manual calculating device using rods, also known as Napier’s Bone to perform arithmetic calculations. The Napier Bone was also referred as Cardboard Multiplication Calculator. The Napier’s calculating device remained in use till 1890.

3.1.3Slide Rule: The commonly used calculating device known as Slide rule was developed using the concept of Napier’s idea of Logarithms. Slide rule was first built in England in 1632.With the modem slide rule; we can perform simple arithmetic calculations as well as calculate square roots, cosine, logs, sine and tangent etc. The slide rule was used till in the middle 1970s.

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3.2 Mechanical Era (1642-1662): Mechanical era starts with the work of Wilhelm Schickard.He built the first mechanical calculator in 1642, which was actually the calculating clock. It was able to work with six digits and carried digits across columns. The details of other different notable devices invented during this era are given below: 3.2.1 Calculating device of Blaise Pascal: In 1642, reputed Mathematician Blaise Pascal of France, at the age of 19, invented the mechanical calculating machine called Pascaline as an aid for his father who was a tax collector. It used arithmetic calculations like addition, subtraction, multiplication and division and displayed the numbers by rotation of different wheels or gears. Each wheel rotated in steps and a wheel completed one rotation in 10 steps. The Pascal’s calculating machine could perform the addition and subtraction operations directly but the multiplication and division operations were performed by repeated additions and subtractions. Blaise Pascal’s calculating machine was the first mechanical calculator. It had the capacity for eight digits and used a series of wheel or gear each number from 0 to 9(base 10), but had trouble carrying and its gears tends to jam. Although, this machine could perform addition and subtraction on whole numbers, it was too expensive and only Pascal could repair it.

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Calculating device of Gottfried Von Leibniz (1646-1716):

In 1671, a German mathematician Gottfried Von Leibniz developed first calculator for multiplication as well as for simple arithmetic calculations. This calculating machine was similar to Pascal’s calculating machine but it was more reliable and accurate. Actually, the Leibniz’s calculating machine was the modified form of the

Pascal’s calculating machine. 3.2.3Punched card system of Joseph Marine Jacquard(1785-1870): Joseph Marine Jacquard, an engineer of France, Invented the machine called a Jacquard loom(1801) used in weaving. It was a “programmable” manufacturing device. It was the first machine that used punched cards with stored information: for example it had different weaving patterns such that the same patterns would be utilized over and over again to get the same product. The ability of his machine to store information contributed a lot to the computer evolution and the textile industry. This automated loom machine operated by COMPUTER Project

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dropping needles through holes punched in cards. The automated loom is considered as the “TRUE DIGITAL COMPUTER”. The punched card system later applied to the US census and then to the

computer. 3.2.4 Calculating device of Charles Xavier (1785-1870): In 1820, a scientist of France, Charles Xavier invented a calculating machine that could perform simple arithmetic calculations such as addition, subtraction, multiplication and division. This calculating machine was named as Arithmometer.

3.2.5 Calculating device of Charles Babbage (1791-1871): In 1882, the English Mathematician Charles Babbage, at Cambridge University, U.K, proposed a steam driven calculating machine having the size of the room, which he called the Difference engine. This machine was able to compute tables of numbers, such as logarithm tables. Ten years later the device was still nowhere near complete, acrimony abounded between all involved and funding dried up. The device was never finished. Babbage was not deterred, and by then he was on to his next brainstorm, which he called the Analytic engine. This device was large as a house and powered by six steam engines. Babbage who made an important intellectual leap regarding the punched card, the presence or absence of each hole in the card physically allowed a colour threads to pass or stop that thread cut. The Analytic engine also had a key function that distinguished computers from calculator. Analytic engine had several features including provisions for inputting data, storing information, performing arithmetic calculations and printing out results which are also found in modern computer. Analytical engine provided the foundation for the modern computer. Therefore, Charles Babbage is known as the Father of modern computer.

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Difference engine

Analytical engine

3.2.6 Lady Augusta Ad (1816-1852): A lady student Augusta Ada Byron, though she was only 19, heard a lecture about the difference engine designed by Charles Babbage and was fascinated by Charles Babbage’s ideas. Therefore, through letters and meetings with Babbage she learned enough about the design of the Analytic engine to begin fashioning programs for the still un-built machine. Ada wrote a series of “Notes” where in she detailed sequences of instructions she had prepared for the Analytic engine. Therefore, Ada earned her spot in history as the first computer programmer. The programming language Ada is named after her. Ada also invented the subroutine and was the first to recognize the importance of looping.

3.3 Electromechanical Era (1890-1945) : The end of the Mechanical era occurred when physics paved the way for electrical innovations. Scientist discovered electrical charge as a way to represent data. Since both the electrical and mechanical components were used, this era is known as electro-mechanical era. The details of different devices invented during this era are given below: 3.3.1 Punched cards by Herman Hollerith (1860-1929): In 1890, an American Scientist Herman Hollerith used the idea of punched card system and introduced the punched cards as input media in computer. He developed the first electromechanical punched card tabulator. This machine could read information that had been punched into cards. These cards were maintained in stack form. Solutions to different problems could be stored on different stacks of cards and accessed when needed. Invention of punched card opened a gate to modern data processing. IBM and other computer manufactures came in this field and started production of computer s that could use punched cards as input media. Data were fed through punched cards. The punched cards provided a means of input/output (I/O), and memory storage. 3.3.2 Attanasoft Berry Computer: In 1939, Dr John Attanasoft, a professor of lowa state university and his assistant, Clifford Berry designed an electronic machine to solve mathematical problems. It was called the Attanasoft-Berry Computer or ABC (Attanasoft and Berry Computer).The Boolean algebra was applied for designing the circuit’s model of this computer. The development of working model of ABC was completed in 1942. In this computer, 45 vacuum tubes were used for performing internal logic operations and capacitors were used for internal storage of data.

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3.3.3 Boolean Algebra: Boolean algebra is the algebra of the logic. It was introduced by English Mathematician George Boole in 1847 for designing logic circuits inside the computer. The Boolean algebra’s rule is used to design the circuits inside the chips. The design of a particular circuit is based on a set of logical statements. 3.3.4 Mark-1 or ASCC: In 1944, an American Dr Howard Aiken, a professor of Harvard University, designed first fully automatic calculating machine. It was named as Mark-1. It is also known as ASCC (Automatic Sequence controlled calculator). This calculating machine operated under the control of given instructions. The instructions were given to this machine with the help of punched paper tape. The Mark-1 remained in operation till 1959.Although, Mark-a proved to be extremely reliable, but it was very complex in design and huge in size. It was 50 feet long and 8 feet high. It was basically, an electromechanical device in which both electronic and mechanical components were used.

3.4. Electronic Era (1946-today): Electronic era begins with the invention of the first real computers as a result of convergence of technology, people, and motivation. The development of electronic era is often described to in reference to the different generations of computing devices. Some of the machines developed during this era are described below: 3.4.1 ENIAC: ENIAC stands for “Electronic Numerical Integrator and Calculator”. It was the first all-electronic computer. It was developed in 1943 by JP Eckert and John Macule at the Moore School of Engineering, University of Pennsylvania in USA. It contained about 18000 vacuum tubes and occupied more than 1500 square feet with weight of 30 tons. The ENIAC was programmed by physically connecting electrical wires in the proper order. It was very difficult to detect errors and to change the program. It could store and manipulate limited amount of data. So its use was limited.

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3.4.2 EDVAC: The ENIAC was programmed by physically connecting electrical wires in the proper order. The operation of ENIAC was very difficult due to its wiring boards. This problem was overcome by a new concept of stored program presented by John Von Neumann. John Von Neumann gave an idea that an idea that a computer should have a very simple, fixed physical structure, and yet be able to perform any kind of computation. Von Neumann idea usually referred to as the stored-program technique. EDVAC stands for Electronic Discrete Variable Automatic Computer. It was designed on stored program. The programs and data were fed in this computer through punched paper tape. The machine mainly served as a laboratory model to test many of the notions of programming and coding used in modern computer.He also introduced the idea of storing both instructions and data in the binary form. His theory was universally adopted. So computing and programming became much faster and efficient.

3.4.3 EDSAC: EDSAC stands for “Electronic Delayed Storage Automatic Computer”. It was developed in 1949 at Cambridge University by groups of scientist headed by Professor Maurice Wilkes. 3.4.4UNIVAC: UNIVAC stands for “Universal Automatic Computer”. It was developed by J.P Eckert and John Macule in 1951. It was the first digital computer. The programs and data were fed in this computer through magnetic tape. In 1952, the International Business-Machine Corporation introduced the 701 commercial computers. After this, improved models of UNIVAC and other 700-series machines were introduced.

4. Generations of computer: The term generation indicates the stages of evolution of development of computers based on the type of technology used in the computer construction over a period of a time. Depending upon the device technology, system architecture, processing mode and language used, computers are broadly categorized into five generations: 4.1 First Generation Computers (1940-1956): The computers developed between 1940-1956were the first generation computers. In these generations Vacuum tubes were used for electrical current flow between electrodes and magnetic drums for memory. Entire machine is dedicated to a particular job until the completion of task. In this generation everything was handled manually by the human operator.

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a) Vacuum tubes for circuitry and magnetic drum for primary memory. b) Punched card for input. c) Printout display for output. d)Used machine language. e) Slow and expensive. f) Generate large amount of heat. g)Large in size. h)Limited storage capacity(1KB-4KB) i) Magnetic tape for storage memory(Secondary memory). Example: ENIAC, EDVAC, UNIVAC .

Advantages: 1)These computers were the fastest of their times. 2)They were programmed using machine language. 3)The electronic digital computers were introduced due to the vacuum tube technology. Disadvantages: 1) Very big in size. 2) Not reliable. 3) Consumed large amount of energy. 4) Very slow in speed. 5) More heat generated and air conditioning was required. 6) More costly. 7) Limited commercial use. 8) Non portable and occupied large space. 9) Difficult to program. 4.2 Second Generation Computer (1956-1965): The transistors technology was used in second generation computers. The electronic component transistors were invented in 1948 at Bell laboratories. The transistors are small in size, fast and more reliable than vacuum tubes. Multiple users were capable of using the machine concurrently. Computer was used manually by the operator.

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Features: 1) Transistors used for electric circuitry. 2) Magnetic core memory for internal storage. 3) Printout for output. 4) Punched card for input. 5) Less amount of heat generated by the computer. 6) Reduced size and cost of a computer. 7) Magnetic tape for external storage. 8) At beginning assembly level language was used and at the end high level language (COBOL, FORTAN) was used. 9) Example: IBM 1401, 7030, 7050, GE 635, 200, 400 Series. Advantages: 1) Low cost. 2) Smaller in size. 3) Fast in size. 4) Less heat generated, more reliable and accurate in calculations. 5) Consumed low power. 6) Used for commercial purposes. 7) Portable than first generation. 8) Assembly language was introduced. The language was easy to write program than machine language. Disadvantages: 1) Air conditioning was required. 2) 2) Commercial production was difficult and these were very costly. 3) Only used for especial purpose. 4) Constant maintenance required. 4.3 Third Generation Computer (1965-1973): The computer developed between 1965-1973 was the third generation computers. In this generation Integrated circuit (IC) were used for the memory and processing unit. Many transistors were placed on a Silicon chip, which drastically change the speed and efficiency of computers.

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Features: 1) IC was used for the memory and processing unit. 2) Semiconductor memory for internal storage. 3) Keyboard for input. 4) Monitor for output. 5) 5) Started using operating system. 6) Processor speed in nanosecond. 7) Used high level language. 8) Magnetic disk for external storage. 9) Minicomputer introduced. Example: IBM 360 & 370 series, CDC-7000 and 7600 series. Advantages: 1) Smaller in size. 2) Production cost was low. 2) 3) More reliable. 4) Easily portable. 5) Easy to operate and upgrade. 3) 6) Low amount of heat is generated. 7) High level language was used. 8) Low power consumption. 4) 9) Widely used for various commercial applications all over the world. 10) Magnetic disk for external storage. Disadvantages: 1) Air conditioning requires. 2) Highly Sophisticated technology required for manufacturing chips. 4.4 Fourth Generation computer (1973-1991): The computers developed between 1973-present were the fourth generation computers. The significant distinction of the fourth generation computer is the development of LSI and VLSI (Thousand and hundred thousand transistors on single chip). These developments were followed by creation of microprocessor.

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Features: 1) Microprocessor having LSI and VLSI technology. 2) Semiconductor memory. 3) Storage capacity drastically increased. 4) Smaller in size. 5) Very user friendly. 6) High speed processor. 7) 4GL language was used. 8) Introduced microcomputers. Example: IBM PCs, Macintosh PCs, Alpha. Advantages: 1) Smaller in size. 2) Production cost is low. 3) Very reliable. 4) Hardware failure is negligible. 5) Totally general purpose. 6) Air conditioning not compulsory. 7) Very high processing speed. 8) Very large internal and external storage capacity. 4.5 Fifth generation computer (Present and beyond): Computers based on Artificial Intelligence (AI) are known as fifth generation computer. This generation computers are capable of billions of calculations per second and they can “think” and “reason” with further specialization of computer hardware. AI in action is the use of expert system. AI expert system is software package that attempts to encode the knowledge and decisions rules established by human specialists so that package users can call on this expertise in making their own decisions. Features: 1) Use of ULSI (Millions of transistors in chip) technology. 2) AI programming (PROLOG and LISP). 3) Knowledge based problem solving technique. 4) High performance multiprocessor system. 5) Input and output in the form of speech and graphics images. COMPUTER Project

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6) Vision system in computer. 7) Having capabilities of learning and reason 10) Able to understand natural languages like English, Japanese, Nepali. Example: Fictional Hall 9000. 2. CLASSIFICATION OF COMPUTER Classification means a system of arranging something in different groups according to their common characters or operating principles. Computers, also can be classified based on their processing speed, amount of data that they can hold, purpose of the computer and working principles. Computers are classified in various ways. They are as follow: 2.1On the basis of Working Principle: 2.1.1 Analog Computers: An analog computer is a form of computer that uses the continuously changeable aspects of physical phenomena such as electrical, mechanical, or hydraulic quantities to model the problem being solved. In contrast, digital computers represent varying quantities symbolically, as their numerical values change. As an analog computer does not use discrete (exact) values, but rather continuous (approximate) values, processes cannot be reproduced with exact equivalence, as they can with Turing machines. The development of transistors made electronic analog computers practical, and until digital computers had developed sufficiently, they continued to be commonly used in science and industry. Analog computers can have a very wide range of complexity. Slide rules are the simplest, while naval gunfire control computers. Accuracy of an analog computer is limited by its computing elements as well as quality of the internal power and electrical interconnections. The precision of the analog computer readout was limited chiefly by the precision of the readout equipment used, generally three or four significant figures. Precision of a digital computer is limited by the word size; arbitrary-precision arithmetic, while relatively slow, provides any practical degree of precision that might be needed.

2.1.2Digital computer: A computer that performs calculations and logical operations with quantities represented as digits, usually in the binary number system is called digital computer. It operates on data, including magnitudes, letters, and symbols, that are expressed in binary form i.e., using only the two digits 0 and 1. By counting, comparing, and manipulating these digits or their combinations according to a set of instructions held in its memory, a digital computer can perform such tasks as to control industrial processes and regulate the operations of machines; analyse and organize vast amounts of business data; and simulate the behaviour of dynamic systems (e.g., global weather patterns and chemical reactions).

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2.1.3 Hybrid computer: Hybrid computers are computers that exhibit features of analog computer and digital computer. The digital component normally serves as the controller and provides logical operations, while the analog component normally serves as a solver of different equations. In general, analog computer are extraordinarily fast, since they can solve most complex equations at the rate at which a signal traverses the circuit, which is generally an appreciable fraction of the speed of light. On the other hand, the precision of analog computers is not good; they are limited to three, or at most, four digits of precision. Hybrid computers can be used to obtain a very good but relatively imprecise 'seed' value, using an analog computer front-end, which is then fed into a digital computer iterative process to achieve the final desired degree of precision. With a three or four digit, highly accurate numerical seed, the total digital computation time necessary to reach the desired precision is dramatically reduced, since many fewer iterations are required. One of the main technical problems to be overcome in hybrid computers is minimizing digitalcomputer noise in analog computing elements and ground systems. 2.2 On the basis of size: 2.2.1 Microcomputer: A microcomputer is a small, relatively inexpensive computer with a microprocessor as its central processing unit (CPU). It includes a microprocessor, memory, and input/output (I/O) facilities. Microcomputers became popular in the 1970s and 80s with the advent of increasingly powerful microprocessors. The predecessors to these computers, mainframes and mini computers were comparatively much larger and more expensive (though indeed present-day mainframes such as the IBM system machines use one or more custom microprocessors as their CPUs). Many microcomputers (when equipped with a keyboard and screen for input and output) are also personal computers (in the generic sense). The term microcomputer came into popular use after the introduction of the minicomputer. Most notably, the microcomputer replaced the many separate components that made up the minicomputer's CPU with one integrated microprocessor chip. Microcomputers are designed to serve only one user at a time, although they can often be modified with software or hardware to concurrently serve more than one user. Microcomputers fit well on or under desks or tables, so that they are within easy access of users. A microcomputer comes equipped with at least one type of data storage, usually RAM. Although some micro-computers (particularly early 8-bit home micros) perform tasks using RAM alone, some form of secondary storage is normally desirable. 2.2.2 Minicomputer: A minicomputer, a term no longer much used, is a computer of a size intermediate between a microcomputer and a mainframe. Typically, minicomputers have been stand-alone computers (computer systems with attached terminals and other devices) sold to small and mid-size businesses for general business applications and to large enterprises for department-level operations. In recent years, the minicomputer has evolved into the "mid-range server" and is part of a network. Computer that is smaller, less expensive, and less powerful than a mainframe or supercomputer, but more expensive and more powerful than a personal computer. Minicomputers are used for scientific and engineering computations, business-transaction processing, file handling, and database management, and are often now referred to as small or midsize servers. IBM's AS/400e is a good example. In an ascending hierarchy of general computer sizes, we find: COMPUTER Project

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      

The embedded systems programming computer, which is embedded in something and doesn't support direct human interaction but nevertheless meets all the other criteria of a microcomputer The workstation, as used to mean a more powerful personal computer for special applications The minicomputer The cluster, which is often several microcomputers or larger computers that share a workload and back each other up The mainframe computer, which is now usually referred to by its manufacturers as a "large server" The supercomputer, formerly almost a synonym for "Cray supercomputer" but now meaning a very large server and sometimes including a system of computers using parallel processing The parallel processing system, which is a system of interconnected computers that work on the same application together, sharing tasks that can be performed concurrently.

2.2.3 Mainframe computer: Modern mainframes can run multiple different instances of operating systems at the same time. This technique of virtual machines allows applications to run as if they were on physically distinct computers. In this role, a single mainframe can replace higher-functioning hardware services available to conventional servers. While mainframes pioneered this capability, virtualization is now available on most families of computer systems, though not always to the same degree or level of sophistication. Mainframes are designed to handle very high volume input and output (I/O) and emphasize throughput computing. Mainframes also have execution integrity characteristics for fault tolerant computing. A mainframe is an ultra-highperformance computer made for high-volume, processor-intensive computing. They are typically used by large businesses and for scientific purposes. You probably won't find a mainframe in any household. In the hierarchy of computers, mainframes are right below supercomputers, the most powerful computers in the world. Yet a mainframe can usually execute many programs simultaneously at a high speed, whereas supercomputers are designed for a single process. Currently, the largest manufacturers of mainframes are IBM and Unisys. 2.2.4Supercomputer: Supercomputers play an important role in the field of computational science, and are used for a wide range of computationally intensive tasks in various fields, including quantum mechanics, weather forecasting, climate research, oil and gas exploration, molecular modelling (computing the structures and properties of chemical compounds, biological macromolecules, polymers, and crystals), and physical simulations (such as simulation of airplanes in wind tunnels, simulation of the detonation of nuclear weapons, and research into nuclear fusion.

2.2 On the basis of Brand: 2.2.1 IBM PC: International Business Machines abbreviated IBM and nicknamed "Big Blue", is a multinational computer technology and IT consulting corporation headquartered in Armonk, New York, United States. The company is one of the few information technology companies with a continuous history dating back to the 19th century. IBM manufactures and sells computer hardware and software (with a focus on the latter), and offers infrastructure services, hosting services, and consulting services in areas ranging from mainframe computers to nanotechnology. Ginni Rometty is the president and CEO of IBM. IBM has been well known through most of its recent history as one of the world's largest computer companies and systems integrators. With over 433,362 (2012) employees worldwide, IBM is one of the largest and most profitable information technology employers in the world. IBM holds more patents than any other U.S. based Technology COMPUTER Project

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Company and has eleven research laboratories worldwide. The company has scientists, engineers, consultants, and sales professionals in over 170 countries. IBM employees have earned five Nobel Prizes, four Turing Awards, five National Medals of Technology, and five National Medals of Science. 2.2.2 IBM compatible: IBM PC compatible computers are those generally similar to the original IBM PC, XT, and AT. Such computers used to be referred to as PC clones, or IBM clones. They duplicated almost exactly all the significant features of the PC architecture, facilitated by various manufacturers' ability to reverse engineer the BIOS using a "clean room design" technique. Columbia Data Products built the first clone of the IBM personal computer by a clean room implementation of its BIOS. The term 'IBM PC compatible' is not commonly used presently because all current mainstream computers are based on the PC architecture, and IBM no longer makes PCs. The competing designs have either been discontinued or, like the Amiga, have been relegated to niche, enthusiast markets. One notable exception was Apple Inc., the Macintosh set of computers of which used non-Intel processors from its inception; first the Motorola 68000 family, then the PowerPC architecture until 2006, when Apple adopted the Intel x86 architecture. Macs (Computers manufactured by Apple) for OS X (OS 10) are capable of running Microsoft Windows. 2.2.3 Apple/Macintosh computers: The Macintosh marketed as Mac, is a line of personal computers (PCs) designed, developed, and marketed by Apple Inc. It is targeted mainly at the home, education, and creative professional markets. The original Macintosh was the first successful personal computer to use a graphical user interface devoid of a command line. It used a desktop metaphor, depicting real-world objects like documents and a trashcan as icons on screen. There are many different Macintosh models, with varying degrees of speed and power. All models are available in many different configurations. All models since 1994 are based on the PowerPC microprocessor. In fact, some analysts say that the entire evolution of the PC can be viewed as an effort to catch up with the Apple Macintosh. In addition to inventing new technologies, Apple also has often been the first to bring sophisticated technologies to the personal computer. 3 Logic Function and Boolean algebra: 3.1 Digital Logic: For two binary variables (taking values 0 and 1) there are 16 possible functions. The functions involve only three operations which make up Boolean algebra: AND, OR, and COMPLEMENT. They are symbolically represented as follows:

These operations are like ordinary algebraic operations in that they are commutative, associative, and distributive. There is a group of useful theorems of Boolean algebra which help in developing the logic for a given operation.

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Single Variable Theorems

3.2 Boolean Algebra: Boolean algebra has been fundamental in the development of computer science and is yet the basis of the abstract description of digital circuits. It is also used in digital logic, computer programming, set theory, and statistics. Boole's algebra predated the modern developments in abstract algebra and mathematical logic; it is however seen as connected to the origins of both fields. In an abstract setting, Boolean algebra was perfected in the late 19th century by Jevons, Schröder, Huntington, and others until it reached the modern conception of an (abstract) mathematical structure. Whereas, in elementary algebra, the variables represent mainly numbers, in Boolean algebra, the variables represent the truth values false and true, which are identified with the bits (or binary digits) and denoted by 0 and 1. They should not be confused with the integers 0 and 1, but may also identify with the elements of the field with two elements. The term "algebra" denotes both a subject, namely the subject of algebra, and an object, namely an algebraic structure. Whereas the foregoing has addressed the subject of Boolean algebra, this section deals with mathematical objects called Boolean algebras, defined in full generality as any model of the Boolean laws. We begin with a special case of the notion definable without reference to the laws, namely concrete Boolean algebras, and then give the formal definition of the general notion. 3.2.1 NOT operation: In digital logic, an inverter or NOT gate is a logic gate which implements logical negation.

The NOT gate is an electronic circuit that produces an inverted version of the input at its output. It is also known as an inverter.If the input variable is A, the inverted output is known as NOT A. This is also shown as A', or A with a bar over the top, as shown at the outputs. 3.2.2 AND Gate: The AND gate is an electronic circuit that gives a high output (1) only if all its inputs are high. A dot (.) is used to show the AND operation i.e. A.B. Bear in mind that this dot is sometime omitted i.e. AB.

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3.2.3 OR Gate: The OR gate is an electronic circuit that gives a high output (1) if one or more of its inputs are

high. A plus (+) is used to show the OR operation.

3.2.4 NAND Gate: This is a NOT-AND gate which is equal to an AND gate followed by a NOT gate. The outputs of all NAND gates are high if any of the inputs are low. The symbol is an AND gate with a small circle on the output. The small circle represents inversion.

3.2.5 NOR Gate: This is a NOT-OR gate which is equal to an OR gate followed by a NOT gate. The outputs of all NOR gates are low if any of the inputs are high. The symbol is an OR gate with a small circle on the output. The small circle represents inversion.

3.2.6 Exclusive OR Gate (XOR) : The 'Exclusive-OR' gate is a circuit which will give a high output if either, but not both, of its two inputs are high. An encircled plus sign ( ) is used to show the EOR operation.

3.2.7 Exclusive NOR Gate (XNOR) : The 'Exclusive-NOR' gate circuit does the opposite to the EOR gate. It will give a low output if either, but not both, of its two inputs are high. The symbol is an EXOR gate with a small circle on the 19 sanjayachauwal.wordpress.com COMPUTER Project

output. The small circle represents inversion.

The NAND and NOR gates are called universal functions since with either one the AND and OR functions and NOT can be generated. Note: A function in sum of products form can be implemented using NAND gates by replacing all AND and OR gates by NAND gates. A function in product of sums form can be implemented using NOR gates by replacing all AND and OR gates by NOR gates. To develop a NAND gate logic system which follows a particular truth table, start by writing logic statements for each line in the truth table for which the output is '1'. These statements are linked by OR. The logic statements are converted into a network of gates including AND, OR, NOT where appropriate. These gates are substituted by their NAND gate equivalents. Finally, any double NOT gates are removed to give a NAND only circuit.

Logic gates representation using the Truth table:

4. Computer System: In computer science and engineering, computer architecture is the art that specifies the relations and part of a computer system. In the architecture of buildings, this art is normally visual, but computer architecture is logical, defining systems to serve particular purposes. In both instances (building and computer), a complete design has many details, and some details are implied by common practice.

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For example, at a high level, computer architecture is concerned with how the central processing unit (CPU) acts and how it uses computer memory. Some fashionable (2011) computer architectures include cluster computing and Non-Uniform Memory Access. Computer architects use computers to design new computers. Emulation software can run programs written in a proposed instruction set. At this stage, while the design is very easy to change, compiler designers often collaborate with the architects, suggesting improvements in the instruction set. Modern emulators may measure time in clock cycles, estimate energy consumption in joules, and give realistic estimates of code size in bytes. These affect the convenience of the user, the life of a battery, and the size and expense of the computer's largest physical part: its memory. That is, they help to estimate the value of a computer design. Levels of the computer Architecture The levels of computer architecture can be classified as: 7 6 Software level 5 4 3 Hardware level 2 1 (A)Hardware level:

Application layer Translator Operating system Machine level Micro-programmed level Digital logic Level Electrical and electronic component

1. Machine level: Machine code or machine language is a system of impartible instructions executed directly by a computer's central processing unit (CPU). Each instruction performs a very specific task, typically either an operation on a unit of data (in a register or in memory, e.g. add or move), or a jump operation (deciding which instruction executes next, often conditional on the results of a previous instruction). Every executable program is made up of a series of these atomic instructions. Machine code may be regarded as an extremely hardware dependent programming language or as the lowest-level representation of a compiled and/or assembled computer program. While it is possible to write programs in machine code, because of the tedious difficulty in managing CPU resources, it is rarely done today, except for situations that require the most extreme optimization. 2. Digital logic level: Digital electronics, or digital (electronic) circuits, represent signals by discrete bands of analog levels, rather than by a continuous range. All levels within a band represent the same signal state. Relatively small changes to the analog signal levels due to manufacturing tolerance, signal attenuation or parasitic noise do not leave the discrete envelope, and as a result are ignored by signal state sensing circuity.In most cases the number of these states is two, and they are represented by two voltage bands: one near a reference value (typically termed as "ground" or zero volts) and a value near the supply voltage, corresponding to the "false" ("0") and "true" ("1") values of the Boolean domain respectively. 3. Electrical and electronic level: Now a day’s most of the modern and fantastic computers devices are built from the simple electronic components such as diode, transistors, capacitors, resistors, or the components in I.C forms. These components are based on the power supplies. 4. Micro program level: COMPUTER Project

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a type of hierarchical control of digital computer operation in which each instruction refers to a sequence of microinstructions, which are usually at a lower level than the instruction itself. A set of microinstructions is known as a microprogram and is usually stored in the read-only memory of a computer, which is an integral part of the control equipment. The microinstructions recorded in the memory control the operation of the entire computer’s hardware by selecting the required set of elementary computer operations at every step, and the sequence of microinstructions ensures that a given instruction is carried out. (b) Software level: 1. Application software Application software, also known as an application or an app, is computer software designed to help the user to perform specific tasks. Examples include enterprise software, accounting software, office suites, and graphics software and media players. Many application programs deal principally with documents. Applications may be bundled with the computer and its system software, or may be published separately. In recent years, the abbreviation "app" has specifically come to mean application software written for mobile devices, with the abbreviation in particular representing both the smaller size and smaller scope of the software (i.e. an app whose sole purpose is to display an image representation of the current weather). 2. System software: System software refers to the files and programs that make up your computer's operating system. System files include libraries of functions, system services, drivers for printers and other hardware, system preferences, and other configuration files. The programs that are part of the system software include assemblers, compilers, file management tools, system utilities, and debuggers. The system software is installed on your computer when you install your operating system. You can update the software by running programs such as "Windows Update" for Windows or "Software Update" for Mac OS X. Unlike application programs, however, system software is not meant to be run by the end user. For example, while you might use your Web browser every day, you probably don't have much use for an assembler program (unless, of course, you are a computer programmer). Operating system: An operating system, or "OS," is software that communicates with the hardware and allows other programs to run. It is comprised of system software, or the fundamental files your computer needs to boot up and function. Every desktop computer, tablet, and Smartphone includes an operating system that provides basic functionality for the device. Common desktop operating systems include Windows, Mac OS X, and Linux. While each OS is different, they all provide a graphical user interface, or GUI, that includes a desktop and the ability to manage files and folders. They also allow you to install and run programs written for the operating system. While Windows and Linux can be installed on standard PC hardware, Mac OS X can only run on Macintosh computers. Therefore, the hardware you choose affects what operating system(s) you can run. Mobile devices, such as tablets and Smartphone also include operating systems that provide a GUI and can run applications. Since the operating system serves as a computer's fundamental user interface, it significantly affects how you interact with the device. Therefore, many users prefer to use a specific operating system. For example, one user may prefer to use a computer with Mac OS X instead of a Windows-based PC. Another user may prefer an Android-based Smartphone instead of an iPhone, which runs on iOS. Translator:

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An individual or a computer program that renders a text into another language is called a translator. The discipline concerned with issues related to the production of translations is called translation studies. Programming language processor (assembler, compiler, or interpreter) that converts a computer program written in one language to another.it is used to convert high level language to machine level language. System buses

Fig:Diagram of system buses Example of a single system computer bus: Bus is a group of wires that connects different components of the computer. It is used for transmitting data, control signal and memory address from one component to another. A bus can be 8 bit, 16 bit, 32 bit and 64 bit. A 32 bit bus can transmit 32 bit information at a time. A bus can be internal or external. A system bus is a single computer bus that connects the major components of a computer system. The technique was developed to reduce costs and improve modularity. It combines the functions of a data bus to carry information, an address bus to determine where it should be sent, and a control bus to determine its operation. Although popular in the 1970s and 1980s, modern computers use a variety of separate buses adapted to more specific needs. Types of bus:

 Data bus: Data bus carries data from on component to another. It is uni-directional for input and output devices and bidirectional for memory and CPU.

 Control bus: Control bus carries control signal. CU of CPU uses control signal for controlling all the components. It is uni-directional from CPU to all other components.

 Address bus: Address bus carries memory address. A memory address is a numerical value used for identifying a memory location. Computer performs its entire task through the memory address. CU of CPU sends memory address to all the components. So, address bus is also uni-directional from CPU to all other components. Information Processing Cycle: To understand how a computer functions you must understand the information processing cycle. What is the information processing cycle? The sequence of events in processing information, which includes (1) input, (2) processing, (3) storage and (4) output. These processes work together and repeat over and over. 1. Input—entering data into the computer. COMPUTER Project

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2. Processing—performing operations on the data. 3. Storage—saving data, programs, or output for future use. 4. Output—presenting the results. The process is described as: This refers to the way information is processed in a computers information management system. The information processing cycle consists of five specific steps: 1. Input: This is any kind of data- letters, numbers, symbols, shapes, images or whatever raw material put in to the computer system that needs processing. Input data is put into the computer using a keyboard, mouse or other devices such as the scanner, microphone and the digital camera. 2. Processing : This is the transformation, sorting, text formatting and editing of data into information by the central processing unit which is a device consisting of electronic circuitry that executes instructions to process data. For instance; when the computer adds 4+4=8 that is an act of processing. 3. Storage Data and information not currently being used must be stored so it can be accessed later. There are two types of storage; primary and secondary storage. Primary storage is the computer circuitry that temporarily holds data waiting to be processed (ROM) and it is inside the computer. Secondary storage is where data is held permanently. A floppy disk, hard disk or CD- ROM is examples of this kind of storage. 4. Output : This is whatever is put out from the computer system as the result of processing. Processed information is output, e.g. numbers or pictures displayed on the monitor, music piped out over some loud speakers or words printed out on a paper in a printer. 5. Communication: Computers nowadays have communication ability which increases their power. With wired or wireless communication connections, data may be input from afar, processed in a remote area and stored in several different places and then be transmitted by modem as an e-mail or posted to the website.

Input II

ALU

Register

Output

Array Control Unit

Main Memory

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1. Data/Instruction/Flow= 2. Command/Control signal Flow= Central Processing Unit (CPU) : The ALU and the CU of a computer system are jointly known as the central processing unit. You may call CPU as the brain of any computer system. It is just like brain that takes all major decisions, makes all sorts of calculations and directs different parts of the computer functions by activating and controlling the operations Arithmetic Logical Unit : After you enter data through the input device it is stored in the primary storage unit. The actual processing of the data and instruction are performed by Arithmetic Logical Unit. The major operations performed by the ALU are addition, subtraction, multiplication, division, logic and comparison. Data is transferred to ALU from storage unit when required. After processing the output is returned back to storage unit for further processing or getting stored. Control Unit (CU) : The next component of computer is the Control Unit, which acts like the supervisor seeing that things are done in proper fashion. Control Unit is responsible for coordinating various operations using time signal. The control unit determines the sequence in which computer programs and instructions are executed. Things like processing of programs stored in the main memory, interpretation of the instructions and issuing of signals for other units of the computer to execute them. It also acts as a switch board operator when several users access the computer simultaneously. Thereby it coordinates the activities of computer’s peripheral equipment as they perform the input and output. Register Array: Array is the memory inside the processor which holds data to be processed and result of the operation temporarily .Registers in cpu are of two types: 1. Specific purpose registers (SPR) Examples: -Memory buffer register,-Memory address registers,-Stack pointer to hold address. 2. General purpose registers (GPR) Examples: -Accumulation to be used in arithmetic,-Counter register to count numbers of repetition of execution,-Base register to store base register. Microprocessor: A microprocessor incorporates the functions of a computer's central processing unit (CPU) on a single integrated circuit (IC), or at most a few integrated circuits. It is a multipurpose, programmable device that accepts digital data as input, processes it according to instructions stored in its memory, and provides results as output. It is an example of sequential digital logic, as it has internal memory. Microprocessors operate on numbers and symbols represented in the binary numeral system. The advent of low-cost computers on integrated circuits has transformed modern society. General-purpose microprocessors in personal computer are used for computation, text editing, multimedia display, and communication over the Internet. Many more COMPUTER Project

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microprocessors are part of embedded systems, providing digital control of a myriad of objects from appliances to automobiles to cellular phones and industrial process control. Microprocessor, electronic circuit that functions as the central processing unit (CPU) of a computer, providing computational control. Microprocessors are also used in other advanced electronic systems, such as computer printers, automobiles, and jet airliners. The microprocessor is one type of ultra-large-scale integrated circuit. Integrated circuits, also known as microchips or chips, are complex electronic circuits consisting of extremely tiny components formed on a single, thin, flat piece of material known as a semiconductor. Modern microprocessors incorporate transistors (which act as electronic amplifiers, oscillators, or, most commonly, switches), in addition to other components such as resistors, diodes, capacitors, and wires, all packed into an area about the size of a postage stamp. A microprocessor consists of several different sections: The arithmetic/logic unit (ALU) performs calculations on numbers and makes logical decisions; the registers are special memory locations for storing temporary information much as a scratch pad does; the control unit deciphers programs; buses carry digital information throughout the chip and computer; and local memory supports on-chip computation. More complex microprocessors often contain other sections—such as sections of specialized memory, called cache memory, to speed up access to external data-storage devices. Modern microprocessors operate with bus widths of 64 bits (binary digits, or units of information represented as 1s and 0s), meaning that 64 bits of data can be transferred at the same time.

The Role of the Microprocessor: Microprocessors contain the parts necessary to allow a computer to handle instructions and data. They attach to the motherboard and require a heat sink and fan to keep cool due to the high speeds at which they process data. Logic: The arithmetic logic unit found in a microprocessor uses a present list of instructions to handle operations such as adding data together, moving data and jumping to another area of code. In this role, the microprocessor turns code into basic instructions the hardware can understand. Memory: Another role of the microprocessor involves handling memory. The microprocessor decides which data goes to the short-term register memory and which data goes to the long-term random access memory. The microprocessor also stores the addresses of any important pieces of data in memory so it can later retrieve them. COMPUTER Project

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Power: Microprocessors channel the power signal through the control unit. The control unit lets the microprocessor know when to fetch and execute the next instruction. The microprocessor can then regulate the speed at which the computer handles instructions, making the computer efficient and consistent.Components of computer system 1. Hardware: Refers to objects that you can actually touch, like disks, disk drives, display screens, keyboards, printers, boards, and chips. In contrast, software is untouchable. Software exists as ideas, concepts, and symbols, but it has no substance. Books provide a useful analogy. The pages and the ink are the hardware, while the words, sentences, paragraphs, and the overall meaning are the software. A computer without software is like a book full of blank pages -- you need software to make the computer useful just as you need words to make a book meaningful. 2. Software: Software means computer instructions or data. Anything that can be stored electronically is software, in contrast to storage devices and display devices which are called hardware. The terms software and hardware are used as both nouns and adjectives. For example, you can say: "The problem lies in the software," meaning that there is a problem with the program or data, not with the computer itself. You can also say: "It's a software problem. “The distinction between software and hardware is sometimes confusing because they are so integrally linked. Clearly, when you purchase a program, you are buying software. But to buy the software, you need to buy the disk (hardware) on which the software is recorded. 3. Data and information: The data are the main section of the input that are given by the user to the computer and the computer implies what to be done. For the meaningful out put the input must be syntactically and semantically correct. 4. User: A user is an agent, either a human agent (end-user) or software agent, who uses a computer or network service. A user often has a user account and is identified by a username (also user name). Other terms for username include login name, screen name (also screen name), nickname (also nick), or handle, which is derived from the identical Citizens Band radio term. Users are also widely characterized as the class of people that use a system without complete technical expertise required to understand the system fully. In hacker-related contexts, such users are also divided into users and power users. 5. Procedure: A procedure is a block of code that performs a single task. It a building block of a computer program but is a somewhat old fashioned phrase as nowadays computer languages use functions not procedures. Procedure is the most important in computer system. 6. Communication: Communication protocols define the rules and data formats for exchanging information in a computer network, and provide the basis for network programming. Well-known communications protocols include two Ethernet, hardware and link layer standard that is ubiquitous in local area networks, and the Internet protocol suite, which defines a set of protocols for internetworking, i.e. for data communication between multiple networks, as well as host-to-host data transfer, and application-specific data transmission formats. COMPUTER Project

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Hardware - Input Devices: The input devices you need to know about are: Keyboard: The most commonly used input device. Some keyboards are specially designed to help people with disabilities. Mouse: Used to control a pointer and to select items. A very user-friendly device.

Trackball: This is like an upside down mouse where the user rolls the wheel in the direction they want the pointer to go. This is useful when there is no flat surface to use a mouse on. They are often used with video games and information kiosks. Trackpad: Used instead of a mouse on most laptop computers. It is a touch sensitive pad that the user moves their finger along in the direction they wish the pointer move.

Joystick: Often used for playing games and for simulators. They can move in 8 directions and often have buttons attached for extra functionality.

Graphics Tablet: Used for Computer Aided Design (CAD) and other graphics work. It is a flat, pressure sensitive board that you press on with a special pen. It makes it easier to draw, just like using a pen or pencil.

Scanners: Used to input what is on paper (hardcopy) into the computer. This includes pictures, photographs and text. Text can be recognized by Optical Character Recognition (OCR) software that examines a scanned image for letters and other characters that it recognizes and then converts it into a document that you can edit. Microphone: Used to input sound. It can be used along with voice recognition software to enter text. The software is "trained" to recognize the way a user speaks and then converts the sounds into text. When using a microphone the computer needs to fitted with a sound card. This contains a processor and RAM used specifically for converting analogue sound to digital and for improving the quality of audio output. COMPUTER Project

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Digital Cameras: Digital cameras are used in just the same way as ordinary film cameras with the exception that the user can look at pictures that have been taken and delete the pictures they not like. Digital Video Camera is commonly used to record video clips.

Webcams: are very basic digital video cameras used to capture images to be sent down networks for video conferencing. Webcams do not allow you to save the images like digital video cameras do. Video conferencing is where people can "meet" across a network using microphones, webcams and monitors. This lets people meet who are different countries meet. OCR (Optical Character Reader): OCR digitizes handwritten or printed text. Printed text will have fewer errors than hand written. It directly converts hand written text into digital text which can be edited. OCR contains predefined format of all the characters. During digitizing process, it creates an image of the character and compares it with stored format to determine the character. MICR: It stands for Magnetic Ink Character Reader. MICR is an OCR that can digitize text written or printed by using magnetic ink like iron oxide or barium ferrite. It is used in security systems and for processing cheque in bank. OMR: It stands for Optical Mark Reader. It is used for answer sheet correction in multiple choice questions. With the use of OMR answer sheet correction will be faster and error free. BCR: It stands for Bar Code Reader. Bar codes are the magnetic lines used for storing the information about the product like manufacturing date, expiry date, company name, etc. BCR is used to read the information stored in bar codes. Bar codes are also used in security system. Microphone: It is an input device for sound. It captures sound wave, converts it into digital format and provides it to the CPU. Common mobile computing devices like PDA, smart phone contains microphone. Card reader: It is used to read the information stored in cards like ATM card, Credit card, Smart card, etc.

Hardware - Output Devices: Monitor: COMPUTER Project

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It is also known as VDU (Visual Display Unit). It is the most basic output device. It is used to display the output. Types of monitor on the basis of color display are: 1.

Monochrome monitor:

It is a single colored monitor. It can display only text and images of a single color against a contrasting background. The first monitor displayed text and images of light green color against black background. 2. Gray scale monitor: It can display 256 different variations of black and white color. It can also display video. The first television set was gray scale. 3. Color monitor: It can display 16-42 million colors. It uses 3 basic colors Red, Blue and Green. All the other colors are the combination of these colors. Color monitor is also known as RGB monitor. Types of monitor on the basis of architecture:

 CRT Monitor: CRT is the large bulky sized monitor. It has high power requirement so it is not appropriate for portable devices. It is cheaper and has better brightness so, it is preferred by graphic designers. Merits of CRT monitor are:    

It has better brightness. It is cheaper in cost. It is more durable. It has better graphics and larger viewing angle (~180)

De-merits of CRT monitor are:    

Due to its high brightness human eyes are negatively affected. It requires high power. It is large in size so occupies more space. It is not portable.

Working mechanism of CRT: A monochrome CRT contains single electron gun which emits beam of electrons. These electrons are attached towards positive phosphorous screen. When an electron strikes the screen it glows and emits light. A small area in which an electron strikes is known as pixel. To display a screen all the pixel are striked by electrons. Accelerating anode varies the speed of the electron and deflecting system changes the path of the electron. COMPUTER Project

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A color CRT monitor contains three electron guns which emits three electrons at a time. These electrons converge in the same pixel to display a color.

 LED: LED contains multiple small bulbs. The contents are displayed by turning the bulbs "on" and "off". Initially it was used only for simple digital displays like in calculator, digital watch, etc. At present it is also used in television, desktop PC, laptop, etc. Merits of LED are:    

It is light in weight so, it can be used in portable devices. It requires less power. It is small in size. Its viewing angle is larger compared to LCD.

De-merits of LED are:  

It has low brightness but is better than LCD and plasma. It is expensive compared to CRT.



It is difficult to maintain.

LCD: LCD contains liquid crystals in between two plates of the screen. The plates are made by either glass or plastic. The front plate is transparent and the back plate is reflective. Liquid crystals are charged electronically to display the content. This monitor is popular for portable devices because of its small size, light weight, low power requirement however it has low brightness and it requires viewing angle of almost 90. Merits of LCD:    

It is small in size. It is light in weight. It has low power requirements so, can be used in portable devices. It is cheaper than LED and plasma display.

De-merits of LCD:   

It has low brightness. It is expensive compared to CRT. It requires viewing angle of almost 90.

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 Plasma display: It contains neon gas in between the two plates of the screen in place of liquid crystals of LCD. It has larger viewing angle but is expensive than LCD. It is smaller in size, light in weight and it has low power requirement and low brightness. Merits of plasma display:   

It is smaller in size and light in weight. It has low power requirement so can be used in portable devices. It has larger viewing angle.

De-merits of plasma display:  

It has low brightness. It is expensive than LCD.

Speaker: Speaker is a soft copy output device for audio. It generates analog sound wave from stored digital sound by using vibrators. Different types of speakers vary on the loudness of sound generated. Some of the speakers used are:

Hard copy output devices: I. Printer: Printer makes the permanent impression of color on the printing material like paper, plastic, clothes, rubber, metal, etc. A printer can be single or multi-colored. Types of printer are: COMPUTER Project

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a. Impact printer: It prints by physically touching the printing material. It is noisier, slower for printing, single colored. It produces low quality output. It is usually cheaper and it can produce multiple copies at the same time by using carbon paper. It uses ink ribbon for printing. 1. Dot matrix printer: It is an impact type character printer. It prints character by the combination of dots where each dot is printed when the hammer strikes the printing material. It can print both image and text of different font and size. It is appropriate for low volume printing. It is usually available in three operating modes: fast, medium and slow. Faster speed will have low printing quality. Merits:  It can print both image and text of different font and size.  Its operating cost is low.  It can print multiple copies at the same time using carbon paper. De-merits:    

It is noisy, slower. It has low printing quality. It can print single color only. It is not appropriate for large volume printing.

2. Daisy wheel printer: It is an impact type character printer. It can only print text of fixed size and font. It contains separate hammer for each character so it is also known as letter quality printer. Its printing quality is better than dot matrix printer. It is faster than dot matrix printer. It is rarely used at present. Merits:  Its printing quality is better than dot matrix printer.  It is faster than dot matrix printer.  It can print multiple copies at the same time using carbon paper.

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De-merits:    

It can print text of fixed size and font. It is noisy, slower than non-impact printers. It can print a single color. It is not appropriate for large volume printing. It can't print images.

c. Line printer: It is an impact type printer. It can print a complete line of text at a time. It can't print images and text of different size and font. It is expensive than non-impact. It is appropriate for continuous printing like printing mark sheet, bill, bank statement, etc. the different line printers are: chain printer, drum printer, band printer. Merits:  It can be used for continuous printing.  It is faster than character printer.  It can print a complete line of text at a time.  It can print multiple copies at a time.



    

b.

De-merits: It can't print images and text of different size and font. Its printing quality is low. It is slower and noisy. It can print a single color. It is expensive.

Non-impact printer:

it prints without touching the printing material. It sprays liquid or powder ink. It uses electromagnetic or electrostatic mechanism. It is noiseless, faster for printing usually expensive, it has high printing quality, it can be single or multi-colour, it cannot produce multiple copies at the same time. 1.Ink jet printer : COMPUTER Project

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It is non-impact type character printer. It uses liquid ink for printing. It can be single or multi-colored. Multicolored ink jet printer can use either RGB colors or CYMK (cyan, yellow, magenta, black). This printer uses dot-matrix approach for printing i.e. a dot is formed by spraying liquid ink. Series of dots are used to print characters and images. It is cheaper to buy but its operating cost is expensive due to expensive ink. So, it is appropriate only for low volume printing. Merits:     

It is not noisy and is faster than impact printers. It can be both single and multi-colored. It is cheaper to buy. It can print both text and images. Its printing quality is better than impact printers.

De-merits:    

Its operating cost is high. It is appropriate for low volume printing only. It can't produce multiple copies at the same time. It is not appropriate for continuous printing.

2. Laser printer: It is non-impact type page printer. It uses powder ink (toner) for printing. It is expensive to buy but its operating cost is low. So, it is appropriate for large volume printing. Multi-colored laser printer is larger in size and they are slower and expensive. It can print about 30 pages per minute. Merits:     

It is not noisy and is faster than impact printer. It can be both single and multi-colored. Its operating cost is low. It can print both text and images. Its printing quality is better than impact printer.

De-merits: 

It is expensive to buy.

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 

It can't print multiple copies at the same time. It is not appropriate for continuous printing.

Thermal Printers: Thermal printers are not used longer in computer. These printers print on special heat sensitive papers which are expensive. The image is produced from small dots which are made on paper by heating up. II Plotter: It is large sized printer. It is used to plot large maps, designs, advertisements, etc. It is multi-colored, slow for printing, expensive and large in size. Paper, plastic (mainly flex) is used as printing material. It uses technology like ink jet technology, color pen technology. Ink jet technology uses liquid ink whereas color pen technology uses multi-colour pens controlled by the mechanical arm. Ink jet is cheaper and colour pen has better printing quality. Different plotters in use are:   

Drum plotter Flatbed plotter Micro grip plotter

Communication port : It is a hardware device used for connecting peripherals devices with the computer. It has major functions like:    

Connecting peripheral devices. Transmitting data to and fro from peripheral devices. Providing electrical power to the small peripheral devices. Some of the communication ports used are:

1. Serial port: It is used for connecting slow speed devices like keyboard, mouse, etc. It also provides electrical power supply to these devices. It can transmit 1 bit data at a time. In computing, a serial port is a serial communication physical interface through which information transfers in or out one bit at a time (in contrast to a parallel port).Throughout most of the history of personal computers, data transfer through serial ports connected the computer to devices such as terminals and various peripherals.

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2. Parallel port It is used for connecting medium speed devices like monitor, printer, etc. It can transmit 8 bit data at a time. A parallel port is a type of interface found on computers (personal and otherwise) for connecting peripherals. In computing, a parallel port is a parallel communication physical interface. It is also known as a printer port or Centronics port. It was a de facto industry standard for many years, and was finally standardized as IEEE 1284 in the late 1990s, which defined a bi-directional version of the port. Today, the parallel port interface is seeing decreasing use because of the rise of Universal Serial Bus (USB) and FireWire (IEEE 1394) devices, along with network printing using Ethernet. The parallel port interface was originally known as the LPT port (Line Print Terminal or Local Print Terminal) on IBM PC-compatible computers.

3. USB (Universal Serial Bus): USB is the common interface developed by multiple hardware developers for supporting large variables of devices. It is used to connect keyboard, monitor, pen drive, etc. It is the most common user interface at present. Universal Serial Bus (USB) is an industry standard developed in the mid-1990s that defines the cables, connectors and communications protocols used in a bus for connection, communication and power supply between computers and electronic devices. USB was designed to standardize the connection of computer peripherals, such as keyboards, pointing devices, digital cameras, printers, portable media players, disk drives and network adapters to personal computers, both to communicate and to supply electric power. It has become commonplace on other devices, such as smartphones, PDAs and video game consoles. USB has effectively replaced a variety of earlier interfaces, such as serial and parallel ports, as well as separate power chargers for portable devices.

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4. IEEE 1394 interface: This interface is used for connecting high speed devices like connecting audio/video equipment’s, aeronautical devices, medical equipment, etc. The IEEE 1394 interface, developed in the late 1980s and early 1990s by Apple as FireWire, is a serial bus interface standard for high-speed communications and isochronous real-time data transfer. The 1394 interface is comparable with USB and often those two technologies are considered together, though USB has more market share. Apple first included FireWire in some of its 1999 models, and most Apple computers since the year 2000 have included FireWire ports, though, as of 2013, nothing beyond the 800 version (IEEE-1394b). The interface is also known by the brand i.LINK (Sony), and Lynx (Texas Instruments). IEEE 1394 replaced parallel SCSI in many applications, because of lower implementation costs and a simplified, more adaptable cabling system. The 1394 standard also defines a backplane interface, though this is not as widely used.

PCI (Peripheral Communications Interface): It is used for connecting peripheral devices like internal modem, internal TV card, sound card, graphics card, etc with the computer. It is available in the mother board. The Serial Peripheral Interface Bus or SPI (pronounced as either ess-pee-eye or spy) bus is a synchronous serial data link standard, named by Motorola that operates in full duplex mode. Devices communicate in master/slave mode where the master device initiates the data frame. Multiple slave devices are allowed with individual slave select (chip select) lines. Sometimes SPI is called a four-wire serial bus, contrasting with three, two, and one-wire serial buses. Memory: Internal storage areas in the computer. The term memory identifies data storage that comes in the form of chips, and the word storage is used for memory that exists on tapes or disks. Moreover, the term memory is usually used as a short hand for physical memory, which refers to the actual chips capable of holding data. Some computers also use virtual memory, which expands physical memory onto a hard disk. Every computer comes with a certain amount of physical memory, usually referred to as main memory or RAM. You can think of main memory as an array of boxes, each of which can hold a single byte of COMPUTER Project

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information. A computer that has 1 megabyte of memory, therefore, can hold about 1 million bytes (or characters) of information. The memory can be classified into : 1. Primary memory / Main memory 2. Secondary memory / Auxiliary memory The memory hierarchy depicts the relationship of memory devices with the CPU depending on the increase in cost, speed and decrease in capacity and size while moving towards CPU. Primary Memory: Primary memory, or storage, is the area of a computer from which the processor can access data quickly. It is active only while the computer is switched on. Primary Storage is where computer programs must be when they are running. The central processing unit can only access programs when they are in primary storage. Programs move in an out of primary storage as they are needed. Primary memory is much smaller than the secondary, more permanent memory, such as a hard disk, CD-ROM or DVD. Originally called core storage, primary memory is a term that originated in the days of big mainframe computers to distinguish it from secondary storage, which required input and output operations for storing and retrieving data. With the arrival of personal computers, primary memory became known as RAM--random access memory. RAM typically contains portions of the operating system as well as applications and data in active or frequent use. The part of the operating system stored in the primary memory is called the kernel. It is the first part that loads when the computer is turned on, and it stays there until the computer is turned off. Random-access memory: Random-access memory (RAM) is a form of computer data storage. A random-access device allows stored data to be accessed in very nearly the same amount of time for any storage location, so data can be accessed quickly in any random order. In contrast, other data storage media such as hard disks, CDs, DVDs and magnetic tape, as well as early primary memory types such as drum memory, read and write data only in a predetermined order, consecutively, because of mechanical design limitations. Therefore the time to access a given data location varies significantly depending on its physical location. Today, random-access memory takes the form of integrated circuits. Strictly speaking, modern types of DRAM are not random access, as data is read in bursts, although the name DRAM / RAM has stuck. However, many types of SRAM, ROM, OTP, and NOR flash are still random access even in a strict sense. RAM is often associated with volatile types of memory (such as DRAM memory modules), where its stored information is lost if the power is removed. Many other types of non-volatile memory are RAM as well, including most types of ROM and a type of flash memory called NOR-Flash. The first RAM modules to come into the market were created in 1951 and were sold until the late 1960s and early 1970s.

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Types of RAM: Dynamic random-access memory: Dynamic random-access memory (DRAM) is a type of random-access memory that stores each bit of data in a separate capacitor within an integrated circuit. The capacitor can be either charged or discharged; these two states are taken to represent the two values of a bit, conventionally called 0 and 1. Since capacitors leak charge, the information eventually fades unless the capacitor charge is refreshed periodically. Because of this refresh requirement, it is a dynamic memory as opposed to SRAM and other static memory.The main memory (the "RAM") in personal computers is dynamic RAM (DRAM). It is the RAM in laptop and workstation computers as well as some of the RAM of video game consoles. The advantage of DRAM is its structural simplicity: only one transistor and a capacitor are required per bit, compared to four or six transistors in SRAM. This allows DRAM to reach very high densities. Unlike flash memory, DRAM is volatile memory (cf. non-volatile memory), since it loses its data quickly when power is removed. The transistors and capacitors used are extremely small; billions can fit on a single memory chip. Static random-access memory: Static random-access memory (SRAM) is a type of semiconductor memory that uses bistable latching circuitry to store each bit. The term static differentiates it from dynamic RAM (DRAM) which must be periodically refreshed. SRAM exhibits data remanence, but it is still volatile in the conventional sense that data is eventually lost when the memory is not powered. Retains its content as long as the power supply is there. Once the power supply is lost it loses its contents.

ROM(Read Only Memory): ROM : Read only memoryROM stands for Read Only Memory. You cannot write anything to ROM. It holds programs used when the computer is switched on that, if lost would make the computer useless.In this type of memory the information is stored permanently, its is not lost after the system shuts down. The advantage of using this memory is that there are some complex functions like translators that are used repeatedly. These functions are permanently stored in the ROM and these instructions are hard wired in ROM so the execution is very fast. There are different types of ROM. They are described below: 

PROM: (Programmable Read only memory). In this the ROM is programmable but only once. It’s just like burning a CD using CD recorder. You have a blank CD you can record whatever you want, after recording you can read it any number of times.

In a strict ROM the device is constructed with the program already inside. But PROM is produced blank. It is programmed only later. The advantage of using PROM is that a company can change the program it is going to store whenever they want without loss of hardware.

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

 

Erasable programmable ROM (EPROM): This type of PROM can be erased and reprogrammed a number of times. Here the chip that holds the memory is exposed through a glass widow. A strong UV light of a particular frequency if shined through this glass window will erase the EPROM. Electrically erasable programmable ROM (EPROM): This PROM can be reprogrammed under software control.

Secondary Memory: Secondary memory refers to storage devices, such as hard drives and solid state drives. It may also refer to removable storage media, such as USB flash drives, CDs, and DVDs. Unlike primary memory, secondary memory is not accessed directly by the CPU. Instead, data accessed from secondary memory is first loaded into RAM and is then sent to the processor. The RAM plays an important intermediate role, since it provides much faster data access speeds than secondary memory. By loading software programs and files into primary memory, computers can process data much more quickly.While secondary memory is much slower than primary memory, it typically offers far greater storage capacity. For example, a computer may have a one terabyte hard drive, but only 16 gigabytes of RAM. That means the computer has roughly 64 times more secondary memory than primary memory. Additionally, secondary memory is non-volatile, meaning it retains its data with or without electrical power. RAM, on the other hand, is erased when a computer is shut down or restarted. Therefore, secondary memory is used to store "permanent” Types of Secondary memory are:  

Magnetic memory Optical memory

Magnetic Memory: Magnetic memory uses the property of magnet for storing data. It is in use since first generations of computer. It contains data storing surface coated by magnetic oxide. Magnetic storage and magnetic recording are terms from engineering referring to the storage of data on a magnetized medium. Magnetic storage uses different patterns of magnetization in a magnetisable material to store data and is a form of nonvolatile memory. The information is accessed using one or more read/write heads. As of 2011, magnetic storage media, primarily hard disks, are widely used to store computer data as well as audio and video signals. In the field of computing, the term magnetic storage is preferred and in the field of audio and video production, the term magnetic recording is more commonly used. Magnetic memory is further divided as:

 Magnetic Drum: Magnetic drum contains a metallic drum coated by magnetic oxide on the outer surface of the drum, data is stored in this surface. It was in use in first and second generations of computer.

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 Magnetic tape: Magnetic tape contains thin plastic ribbon, only one side of the ribbon is used for storing data. The data storing side is coated by magnetic oxide. It is a sequential access memory. So, the data read/write speed is slower. It is mainly used for storing audio, video and back-up data. It is highly reliable. It requires magnetic tape drive for reading and writing data. It has the storage capacity of 100MB-200GB. The width of the ribbon also varies from 4mm-1inch.

 Magnetic disk: Magnetic disk contains a circular disc made of metal or plastic. Both side of the disc is usually used for storing data. The disc is coated by magnetic oxide. The disc is divided into multiple concentric circles known as track. Tracks are further divided into small area known as sectors. Data are stored in sectors. Example: Hard disk, floppy disk, zip disk, super disk, Winchester disk, jaz disk. External computers peripheral: 1.Hard disk: It is used as main storage device of the computer. It uses 2-4 metallic disks (platter). The disk is usually made of aluminum. Both sides of the disk is used for storing data except the upper side of the uppermost disk and lower side of the lowermost disk. The data storing surface is coated by magnetic oxide. Each data storing surface contains separate read/write head. During data read/write process platter rotates at the rate of 3600-15000rpm. Hard disk is also known as hard drive because both data storing disk and data read/write components are combined together. It has the storage capacity of few megabytes to tera byte.

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2.Floppy disk: It contains single plastic disk. Initially it was used as a main storage device but nowadays it is used for carrying data from one computer to another. It requires floppy drive for its operation. It is not reliable as hard disk because the data storing surface is exposed. So, it may be affected by dust.

 Optical Memory: Optical memory uses light beam for its operation. It is developed in fourth generation of computer. It is mainly used for storing audio/video, backup as well as for carrying data. It requires optical drive for its operation. Its read/write speed is slower compared to hard disk and flash memories.Example: CD, DVD, BD a.CD: It stands for Compact Disk. It has storage capacity of 700 MB or approximately 90 minutes of standard audio. CD contains hard circular plastic, single side of this plastic is coated by aluminum alloy. This alloy stores data. It is protected by additional thin plastic covering. CD required CD drive for its operation. Types of CD are: 

 CD-R it is a blank CD in which data can be stored once. After storing data it is converted into CD-ROM.  CD-ROM It cannot be erased or updated  CD-RW it can be erased and used for multiple times.

b.DVD: It stands for Digital Versatile Disk. It has the storage capacity of 4.7GB to 17GB. Its shape and size is similar to CD but the difference in storage capacity is due to different chemical component and data is 43 sanjayachauwal.wordpress.com COMPUTER Project

compressed before storing. It requires DVD drive for its operation. Read/write speed of DVD is slower than that of CD. Types of DVD are:  

DVD-R DVD-ROM

DVD can also be classified as:    

Single sided single layered DVD (4.7GB) Single sided dual layered DVD (7-8GB) Dual sided single layered DVD (9GB) Dual sided dual layered DVD (17GB)

c. Blu –ray disc: It stands for Bluray disk. It has the storage capacity of 25GB-50GB. It requires BD drive for its operation. Its shape and size is similar to CD and DVD. Types of BD are:   

BD-R BD-ROM BD-RW

External memory devices: 

Zip-drive: It is a magnetic memory. It is thee modification of floppy disk. It has the storage capacity of 100MB and 250MB. It requires Zip disk drive for its operation.

 

Jaz-drive: It is also a magnetic memory. It has the storage capacity of 2GB. It also requires separate Jaz disk drive for its operation.

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





Superdisk: It is also a magnetic memory. It has the storage capacity of 120MB. It requires Super disk drive for its operation. Both floppy and super disk can be used in super disk drive. Pendrive: It is a flash memory. It is a semi-conductor memory. It is mainly used for transferring data. It has faster read/write speed compared to magnetic memory. Pen drive has storage capacity of few MBGB. A pen drive is a plug and play device. A pen drive can be connected with the computer through USB port.

Portablehard disk: it is a magnetic hard disk. It can be connected with the computer through the USB port. It is also a plug and play device.

Cache memory : Cache memory is random access memory (RAM) that a computer microprocessor can access more quickly than it can access regular RAM. As the microprocessor processes data, it looks first in the cache memory and if it finds the data there (from a previous reading of data), it does not have to do the more timeconsuming reading of data from larger memory. In addition to cache memory, one can think of RAM itself as a cache of memory for hard disk storage since all of RAM's contents come from the hard disk initially when you turn your computer on and load the operating system (you are loading it into RAM) and later as you start new applications and access new data. RAM can also contain a special area called a disk cache that contains the data most recently read in from the hard disk.

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Introduction to Microsoft Word and Word Processing :

1.1

INTRODUCTION : Let us consider an office scene. Many letters are typed in the office. The officer dictates a letter. The typist first types a draft copy of the letter. The officer goes through it to check mistakes regarding spelling errors, missing words, etc. and suggests corrections. The typist changes the letter as suggested by the officer. This is a simple example of word processing. MS-WORD is a part of the bigger package called MS OFFICE, which can do much more than word processing. In fact when you open up MS OFFICE you will find four main components in it. They are MS-WORD (for word processing), MS EXCEL (for spread sheet), MS ACCESS (for database management) and MS POWERPOINT (for presentation purposes). However, we will limit ourselves to MS-WORD only in this lesson.

1.2 OBJECTIVES: 

start the MS-WORD package

   

advantages and Features of Word Processing some common Word Processing Packages how to invoke Ms-Word learn the capabilities of Ms-Word

1.3

WHAT IS WORD-PROCESSING? Word Processor is a Software package that enables you to create, edit, print and save documents for future retrieval and reference. Creating a document involves typing by using a keyboard and saving it.

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Editing a document involves correcting the spelling mistakes, if any, deleting or moving words sentences or paragraphs. (a) Advantages of Word Processing: One of the main advantages of a word processor over a conventional typewriter is that a word processor enables you to make changes to a document without retyping the entire document. (b) Features of Word Processing: 

Text is typing into the computer, which allows alterations to be made easily.



Words and sentences can be inserted, amended or deleted.



Paragraphs or text can be copied /moved throughout the document.



Margins and page length can be adjusted as desired.



Spelling can be checked and modified through the spell check facility.



Multiple document/files can be merged.



Multiple copies of letters can be generated with different addresses through the mail-merge facility.

 1.4 IMPORTANT FEATURES OF MS-WORD: Ms-Word not only supports word processing features but also DTP features. Some of the important features of Ms-Word are listed below: 

Using word you can create the document and edit them later, as and when required, by adding more text, modifying the existing text, deleting/moving some part of it.



Changing the size of the margins can reformat complete document or part of text.



Font size and type of fonts can also be changed. Page numbers and Header and Footer can be included.



Spelling can be checked and correction can be made automatically in the entire document. Word count and other statistics can be generated.



Word also has the facility of macros. Macros can be either attached to some function/special keys or to a tool bar or to a menu.



It also provides online help of any option.

Conclusion: Though the common trend among us (students) is to take these academic activities as a formal job (which is correct for a different point of view), I really enjoyed doing this project. I started the work the first day I got my copy of assignment and completed 90% excluding printing and binding jobs within a week and spent some days on its moderation. Now, I am satisfied with my project and the report. COMPUTER Project

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My Future Plan: Computer science is my favorite subject and is primary (which doesn’t mean I underestimate other subjects). I am thinking of either becoming a software engineer or doing my graduation with major subject computer science. Bibliography Conceptual Computer (2013),Divya Deurali Prakashan Pvt.Ltd. URLs: http://www.wikipedia.org http://www.webopedia.org https://www.facebook.com/HsebAndSlcReferenceSite sanjayachauwal.wordpress.com

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COMPUTER Project - SEE, NEB , Engineering Notes - WordPress.com

COMPUTER Project - SEE, NEB , Engineering Notes - WordPress.com

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