Computer History

COMPUTER

Defined as an electronic device which senses or accepts input data, perform result operation or computation,decides on the data in apre arranged sequence or program and provides the result as an output, a computer is a fast machine which is used in every walk of life.it is not a new devices Abacus and Napier's Blaise Pascal's calculator.Then it tool different forms.in the middle ages of computer lasting from 1890 to 1944 many useful computing machines were invented.

                                         The modern age of computer science begin since 1944 in which year Mark I I.B.M. ( Internal Business Machine ) was invented.

since the use of binary number in the system they have divide the progress of hardware into five generations.In the first generation lasting from 1946 to 1959 ENIAC was developed as result of military need which occupied    20 x 40 square feet and used 19000 vacuum tubes.The characteristics of

this age are that in computer internal memory system ranged from 1 kilobyte to 8 kilobyte ( 1 kb – 1024 bytes and 1bytes = 8 characters or

information and their processing time ranged from 3 to 10 milliseconds

( 1 milliseconds = 1/1000 seconds).There were too large in size, unretable, and frequent hardware failure occurred.

                          The second generation lasted from 1959 to 1964 Transistors were now invented so they replaced the vacuum tubes.

This improved the processing speed which ranged from 8 kilo byte to 64 kilo bytes.Their processing time also improved to 6 – 10 micro second ( 1second = 1/1000000 sec.) Thecomputers of this age were smaller in size comparatively  much reliable,had less hardware failure.But still they had defects.

        The third generation remained from 1965 to 1971.In this generation integrated circuits were used improvements in the processing time to 9 –10 narro second(1. Narro second 1/1000000000 seconds and in internal seconds and in internal memory system to 1000 kilobytes were the characteristics of this age.Reliability increased, hardware failuer  were

Very  rare.The size become smaller, less consumption of electricity was

Needed and the computers were inexpensive.