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FAEDAT COLLEGE OF TECHNOLOGY

COMPUTER FUNDAMENTAL

BUSARI

OLANREWAJU OLUWASEUN Onike Yaba, Lagos

INTRODUCTION TO COMPUTER

Definition computer is a set of an electronic (device) that accept data as input, process them with the aid of predefine instructions called Program, and produce a useful output for management or any other people uses. The collection of computer equipment is called HARDWARE while the instructions for the process is called SOFTWARE. Computer is an electronic device that transforms data into meaningful information. Data can be anything like marks obtained by you in various subjects. It can also be name, age, sex, weight, height, etc. of all the students in a class. A computer can take in data and process it. It can store the data either in raw form or as processed results and can deliver the raw or processed data to the outside world on demand.

Function of computer

1. It accepts data
2. It stores data
3. It processes data as desired
4. It retrieves the stored data as and
5. It prints the result in desired format.

Characteristics

1. High speed
2. Accuracy
3. Diligence
4. Versatility
5. Storage
6. Programmability

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5. Versatility - A computer is a very versatile machine. - A computer is very flexible in performing the jobs to be done. - This machine can be used to solve the problems related to various fields. - At one instance, it may be solving a complex scientific problem and the very next moment it may be playing a card game. 6. Reliability - A computer is a reliable machine. - Modern electronic components have long lives. - Computers are designed to make maintenance easy. 7. Automation - Computer is an automatic machine. - Automation means ability to perform the given task automatically. - Once a program is given to computer i.e., stored in computer memory, the program and instruction can control the program execution without human interaction. 8. Reduction in Paper Work - The use of computers for data processing in an organization leads to reduction in paper work and results in speeding up a process. - As data in electronic files can be retrieved as and when required, the problem of - Maintenance of large number of paper files gets reduced.

DISADVANTAGES

Following list demonstrates the disadvantages of computers in today's Society.

1. No I.Q - A computer is a machine that has no intelligence to perform any task.

• Each instruction has to be given to computer.
• A computer cannot take any decision on its own. 2. Dependency
• It functions as per a user’s instruction so it is fully dependent on human being 3. Environment
• The operating environment of computer should be dust free and suitable. 4. No Feeling
• Computers have no feelings or emotions.
• It cannot make judgement based on feeling, taste, experience, and knowledge unlike a human being.

Blaise Pascal A French Mathematician, invented a Machine in 1662 made up of gears which was used for adding numbers quickly. This machine was known as Adding Machine (also known as Pascaline ) and was capable of addition and subtraction. In worked on clockwork mechanism principle. The Adding Machine consisted of numerous toothed wheels having unique position value. The rotation wheels controlled the Addition and Subtraction operation. This Machine was capable carry-transfer automatically. Gottfried Willem Leibnitz A German Mathematician, improved the adding Machine and constructed a new machine in 1671 that was able to perform multiplication and division as well. This Machine performed multiplication through repeated addition of numbers. Leibnitz’s machine used stepped cylinder each with nine teeth of varying lengths instead of wheels as was used by Pascal. CALCULATOR Pascaline ) PASCALINE PASCALINE

Joseph Jacquard Manufactured punched cards at the end of American Revolution and used them to control looms in 1801. Thus the entire control weaving process was automatic. The entire operation was under a program’s control. With the historic invention of punched cards, the era of Storing and Retrieving information started that greatly influenced the later invention and advancements. THE LOOM Sir, Charles Babbage (Father of computer) A professor of mathematics, developed a machine called Difference engine in the year 1882. This machine was expected to calculate logarithmic tables to high degree of precision. The difference engine was made to calculate various mathematical functions. The machine was capable of polynomial evolution by finite difference and its operation was automatic multi stop operation.

Herman Hollerith In 1887, an American named Herman Hollerith (1869-1926) fabricated what was dreamt of by Charles Babbage. He fabricated the first electro-mechanical Punched-card tabulator that used punched-cards for input, output and instructions. This machine was used by American department of census to compile their 1880 census data and were able to complete compilation in 3 years which earlier used to take around 10 years. TABULATING MACHINE

(COMPUTER GENERATION)

he term “Computer generation” is often used in relation to the hardware of computers. Each phase of computer development is known as a separate generation of computer. Each phase of development is characterized by type of switching circuits it utilizes. FIRST GENERATION (1940-1956)

Vacuum Tubes

The first computers used vacuum tubes for circuitry and magnetic drums for memory, and were often enormous, taking up entire rooms. They were very expensive to operate and in addition to using a great deal of electricity, generated a lot of heat, which was often the cause of malfunctions. First generation computers relied on machine language, the lowest-level programming language understood by computers, to perform operations, and they could only solve one problem at a time. Input was based on punched cards and paper tape, and output was displayed on printouts. SUMMARY

1. They used vacuum tubes.
2. They were very expensive.
3. Consume more power with limited performance.
4. Magnetic tape / magnetic drum were used for storage.
5. They were heavy and large in size.
6. They generated a lot of heat.
7. Examples: ENIAC - Electronic Numerical Integrator and Calculator, EDVAC – Electronic Discrete Variable Automatic CMP T

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5. They were faster than first generation computers and also less expensive.
6. Magnetic tapes and magnetic disks were used as secondary memory
7. High level languages such as FORTRAN, COBOL
8. Examples: IBM 1404, UNIVAC 1108, IBM 700, Honeywell 400 UNIVAC 1108 THIRD GENERATION (1964-1971) Integrated Circuits The development of the integrated circuit was the hallmark of the third generation of computers. Transistors were miniaturized and placed on silicon chips, called semiconductors, which drastically increased the speed and efficiency of computers. Instead of punched cards and printouts, users interacted with third generation computers through keyboards and monitors and interfaced with an operating system, which allowed the device to run many different applications at one time with a central program that monitored the memory. Computers for the first time became accessible to a mass audience because they were smaller and cheaper than their predecessors.

SUMMARY

1. They used electronic devices called Integrated Circuits (ICs) instead of Transistors.
2. They were smaller in size than second generation computers and also less expensive.
3. They were faster and more accurate than second generation computers.
4. Small Scale Integration and Medium Scale Integration technology were implemented in CPU, I/O processors etc.
5. Faster processors & better performance
6. In the beginning magnetic core memories were used. Later they were replaced by IBM 360 FOURTH GENERATION (1971- Present) Microprocessors The microprocessor brought the fourth generation of computers, as thousands of integrated circuits were built onto a single silicon chip. What in the first generation filled an entire room could now fit in the palm of the hand. The Intel 4004 chip, developed in 1971, located all the components of the computer— from the central processing unit and memory to input/output controls—on a single chip. In 1981 IBM introduced its first computer for the home user, and in 1984 Apple introduced the Macintosh. SUMMARY

SUMMARY

1. They will be intelligent like human beings, and will use Artificial Intelligence for working.
2. They will be able to think and take decisions like us.
3. They will be used in areas such as robotics, designing, defence.
4. Object oriented language like JAVA suitable for internet programming has been developed.
5. Portable note book computers introduced
6. Storage technology advanced – large main memory and disk storage available
7. Introduced World Wide Web. (And other existing applications like e-mail, e Commerce, Virtual libraries/Classrooms, multimedia applications etc.)
8. New operating systems developed – Windows 95/98/XP/LINUX, etc.
9. IBM notebooks, Pentium PCs-Pentium 1/2/3/4/Dual core/Quad core... SUN work stations, Origin 2000, PARAM 10000, IBM SP/2).

CLASSIFICATION OF COMPUTER

Computers can be classified into three major classes as follows:

• By Type
• By Size
• By Purpose

BY TYPE

Computers can be classified into three major classes based on the Mode of data representation used.

1. Analog Computers
2. Digital Computers
3. Hybrid Computers 1. Analog Computers An analog computer is a form of computer that uses continuous physical phenomena such as electrical, mechanical, or hydraulic quantities to model the problem being solved.
   • It operates by measuring rather than counting.
   • It uses continuous signals as input. Examples: Thermometer, Speedometer etc. Thermometer Speedometer

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BY SIZE

The digital computers that are available nowadays vary in their sizes and types. The computers are broadly classified into four categories based on their size and type.

1. Microcomputers
2. Minicomputers
3. Mainframe computers
4. Supercomputer MICROCOMPUTERS Microcomputers are small, low-cost and single-user digital computer. They consist of CPU, input unit, output unit, storage unit and the software. IBM PC based on Pentium microprocessor and Apple Macintosh are some examples of microcomputers. Microcomputers include desktop computers, notebook computers or laptop, tablet computer, handheld computer, smart phones and netbook, (a) Desktop Computer or Personal Computer (PC) - It is the most common type of microcomputer. It consists of three units—keyboard, monitor, and a system unit containing the CPU, memory, hard disk drive, etc. It is not very expensive and is suited to the needs of a single user at home, small business units, and organizations. Apple, Microsoft, HP, Dell and Lenovo are some of the PC manufacturers. (b) Notebook Computers or Laptop - They are portable and have all the features of a desktop computer. The advantage of the laptop is that it is small in

size, can be carried anywhere. Laptops can be placed on the lap while working. Laptops are costlier than the desktop machines. (c) Netbook - These are smaller notebooks optimized for low weight and low cost, and are designed for accessing web-based applications. Netbooks deliver the performance needed to enjoy popular activities like streaming videos or music, emailing, Web surfing or instant messaging. (d) Tablet - Tablet Computer has features of the notebook computer but it can accept input from a stylus or a pen instead of the keyboard or mouse. It is a portable computer. Tablet computer are the new kind of PCs. (e) Handheld Computer or Personal Digital Assistant (PDA) - It is a small computer that can be held on the top of the palm. It is small in size. PDA uses a pen or a stylus for input, Instead of the keyboard. They have a limited memory