IT FUNDAMENTALS.

 

COMPUTER OVERVIEW.

Computer is an electronic device used for storage and processing information. A computer has moved through various states of development and improvement. These states are referred to as generations of computer.

Most computers follow the basic principle of input, process, and output. A computer consists of two components, hardware and software. A computer has various types of files on a storage media: text storage, graphic storage , and audio storage media.

INTRODUCING COMPUTER SYSTEMS

Computer is an electronic device that stores, retrieves, and processes data, and can be programmed with instructions. A is computer is computer is composed of hardware and software, and can exist in a variety of sizes and configurations.

COMPUTER APPLICATIONS

To begin with, you must understand the impact of computers in the world today. Computers are affecting our lives in one way or the other. Airline and railway reservations, telephone and electricity bills, banking , medical diagnoses, weather forecasts... the list of services using computers is almost endless.

You would have probably noticed that some applications of computers have made life much easier for you - your air ticket is now issued in a matter of minutes and your credit card is processed very fast.

You may be suprise to know that the computer cannot perform any task without you. The computer needs to be instructed on exactly what it has to do.

GENERATIONS OF COMPUTER 

While it would not be wrong to say that the evolution of the computer began with the man's need to count, the actual growth, which have come to be called computer generations. Major technological develpments in each generation led to smaller,  cheaper , more powerful and more efficient and reliabble computers.

FIRST GENERATION - 1940 - 1956: VACCUM TUBES.

The first generation computers used valves leading to huge size and cost. The UNIVAC and ENIAC computers are examples of first generation computing devices.

fig 1.1 first generation computer.

The UIVAC was the first commercial computer delivered to a bussiness clients, the U.S census Bureau in 1951.

fig.2.2  second generation computer

 

 SECOND GENERATION - 1956- 1963: transistors

The secon generation computer used transistors. in span of ten years, transistors that were more efficient and cheaper replaced valves.

fig 3.3 third generation computer

THIRD GENERATION COMPUTERS - 1964 - 1971 : Integrated Circuits.

The Third generation computers used intergrated circuits (IC) . in the early sixties, a major breakthrough was achieved when hundreds of transistors could be placed on a single silicon chip. IC became the basis of the third generation.

fig 4.4 fourth generation computer.

FOURTH GENERATION - 1971- PRESENT: microprocessors

 The fourth generation computers used microprocessors. with the introduction of very large scale integration (VLSI), thousands of transistors could be placed on a single chip.

fig 5.5 fifth generation computer

FIFTH GENERATION - PRESENT AND BEYOND: Artificial intellegence

The fifth generation computer tries to infuse intelligence into computer. The development of these computers is still in its infancy, but examples can be cited of various speech recognition systems and robots.