Computer generation: historical division:

Computer generation: historical division:

a. The first generation computers were developed during 1946 to 1958.

b. They used vacuum tube as an electronic circuit and a magnetic drum as a primary storage.

c. They consumed a lot of power and generated a lot of heat.

d. They used machine level language for writing the programs, which was tedious and time consuming.

e. They had low level of accuracy and reliability.

Second generation of Computers:

a. Transistors were used as electronic circuit

b. These computer used magnetic Cores as primary data storage medium

c. These computer were smaller, faster more reliable and more accurate than those of first generation commuter.

d. They required less power and emitted less heat than vacuum tubes.

e. Their operating speed was up to the microseconds

range.

f. The second generation computer were developed

during 1959 to 1964.

g. They used Machine-independent “high level” programming language such as ALGOL,COBOL,FORTRAN etc.for programming. The examples of second generation computers are IBM1620, IBM1401, CDC3600, LEO markIII,400 series, NCR300etc.

h. The transistor was developed by john Bardeen, Walter Brattain and William Shockley in 1947.

Third generation computers:

Third generation computers were developed during 1965 to 1974.

a. They used Integrated Circuits (IC) as electronic circuits. Jack kilby developed the integrated circuit in 1958.

b. They used semiconductor device as a primary storage.

c. They had large storage capacity.

d. Their operating speed was improved to nano-second.

e. They wre more reliable,much smaller in size,easier to operate and less expensive than previous generation computers.

f. They included multi programming, batch and time-sharing operating systems.

g. They extensively used high level programming language included Report Programming Generator (RPG) and Pascal.

h. The example of third generation computers are IBM system /360, IBM370, GE600series, ICT1900 series, NCR (national cash Register) etc.

Fourth Generation of computers:

a. The fourth generation computers were developed during 1975 to 1990.

b. The first microprocessor called Intel 400 was developed by Intel Corporation USA in 1971.

c. These computer use microprocessor chips as electronic circuits.

d. They use semi-conductor for primary memory and magnetic devices like Floppy disk, hard disk and magnetic tape for secondary storage.

e. Forth generation computers are highly reliable and accurate.

f. Their operating speed has been increased to Pico-seconds.

g. Their size has been reduced to micro computer such as desktop and laptop.

h. They can understand many high level languages, and they are user friendly.

i. The example of forth generation computers are IBMPC

Fifth generation of Computer (1991-incomplete)

a.BIO chip and ULSI are used as main components.

b. they have artificial intelligence.

c. they processor non-numerical information such as pictures an graphs.

d. they use a super conductor as a main storage.

e. they are able to understand natural languages.

f. they are using automatic programming computational logic.

The classification of computer on the basic of their speed, reliability, memory device and performance in a certain period is known computer generation.