...s.Businessmen use computers for accounting and bookkeeping, for keeping track of sales and the amount of stock in the arehouse, for string customers names as ell as for figuring out employees ages and printing their paycheques. Banks could hardly do ithout computers noadays to record customers deposits and ithdraals. Engineers use computers to design buildings, bridges, dams and motor vehicles as ell as to keep spaceships and satellites on course. Computers are used at all levels of government for taxation purposes, administrative tasks, controlling traffic, checking air pollution and carrying out population studies.In industry computers control as ell as check machines and robots that make products, turning the machines on or off and adjusting their operations hen necessary. Computers are used to set type for nespapers, magazines and books they help farmers improve their crop yield they aid doctors by analyzing information from diagnostic instruments or lab tests.To put it into a nutshell, the applications of computers are veritably unlimited.Because of the idespread use of computers, the computer industry has become a leading business not only in the USA and Japan but orld-ide. It consists of thousands of companies all over the globe hich manufacture, sell andor lease computer equipment. Moreover, it also includes innumerable firms, both large and small, hich provide users ith hardare, softare as ell as ith consulting and repair services.HARDAREAs I mentioned before a computer is a machine hich can receive, store, handle and send out information. It automatically inputs and processes data and outputs the results. If information is to be processed, it often has to be coded before the computer can accept it. Modern computers are digital, hich means that all information must be converted into binary form. So the only practical processing of information uses to-state logic the to states of the circuits used in digital electronics are generally off and on, and these are represented logically by the symbols 0 and 1. Either state is called a bit, hich stands for binary digit. All information in a computer is stored as groups of bits, and data and programs are also represented by combinations of them. The data result from the information process in the form of electrical pulses. These signals are decoded in order to output information in ords, numbers, pictures or other forms.Generally a computer consists of the central processing unit CPU and peripheral devices, such as input, output and backing storage devices.CPU Central Processing UnitAll the information processing organisation, manipulation, and distribution of information is done here. It consists of three main parts the control unit, the arithmeticlogic unit, and the main store.The main store holds the programs and the data being used. It is divided into small equal sized units called locations, each containing as fe as 8 bits, but often there are 16 or 32 or more. Any location can be accessed directly by using a number called its address. Each location has a different address. Basically there are to types of storesThe RAM Random Access Memory is the orking store of the computer. Its contents must be loaded prior to use from an external device. hile a program is running, the program itself is usually stored here. So are any of the variables used by the program. hen the poer is sitched off, RAM loses its data.General statements information about computers cont.ROM Read only memory Its contents is permanent and does not disappear henever the system is turned off. Nothing can be ritten to ROM. It is used to store programs essential to the normal running of the computer e.g. operating systems, utilities, language, interpreters, etc..The control unit CU directs and coordinates the entire computer system. It fetches program instructions from the main store and causes them to be carried out. It is in charge of executing the instructions in the correct sequence. Its functions involve controlling the inputoutput units, the arithmeticlogic operations and transferring data to and from the storage.The arithmeticlogic unit ALU does calculations and comparisons.Input devicesKeyboard Most data is still typed on keyboards. Circuitry in the keyboardencodes the characters as they are typed inMouse mouse-shaped object designed to fit under the hand hile its movedabout over the table. A ball bearing produces electrical signals,hich are sent to the computer by a cable causing a cursorto move on the screen.Joystick device hich enables the user to control movements on the screenby manoeuvring a small lever.Output devicesScreens A monitor is a high quality vieing unit. It looks like a television setbut accepts a different kind of input signal and has therefore a far steadier,more clearly defined picture.The printer prints either a character, a line or a page at a timenoadays printing is often done ith the help of laser beams.SOFTARESoftare is the general term for programs hich are ritten to help computer users. A program is an ordered set of instructions a computer carries out. Basically there are to different types of programsSystem programs control the performance of a computer system and provide commonly used facilities e.g. operating systems, compilers, interpreters.Application programs allo a computer to be used for a specific application. Most important for the organisation of a computer is its operating system. This consists of a set of programs to provide a background in hich user-programs can be executed. It keeps the computer running ithout the operator having to intervene too much, controls the use of peripherals and the loading and running of programs.According to their purpose programs may be ritten in lo level or high level programming languages. In any case they have to be translated into machine code by another program compiler The program is translated, stored and then executed in machine code as the computer can onlyexecute machine code instructions. Programming languages COBOL,FORTRAN,LOGO,..Background information from nobody to Mr. Microsoft a revolution beginsBill Gates is one ho needs no introduction. Today, he is one of the most famous names in computer softare innovations. The Ne York TimesBill Gates as born in Seattle 1958 in. As a teenager many skills as revealed about him that ould determine the path of his future success in life. Gates began his career in personal computer softare hen he started programming at the age of 13. His first program as for playing tic-tac-toe. At school he anted all the other students to become interested in computers. The first computer at his school didnt even have a screen. For playing his game they typed in their moves on a typriter-style keyboard and then sat around until the results came chug-chugging out of a loud printing device.At the age of 15 Bill Gates built a device to control traffic patterns in Seattle. In 1975 Bill Gates dropped out of Harvard University to rite prog...
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