GENERATION OF COMPUTER

Depending on the device used, system architecture, processing mode and language used in the computers are categorized in the following five generation. In the development of computers there is lot of change from 1946 to 1990. This time is divided in different generations by scientists in a conference in 1962.

First generation computer (1946-1956)

The computer using vacuum tubes as a memory unit are known as first generation computer. The vacuum tube consumes a lot of power. The vacuum tube was developed by Lee Deforest in 1908.

Features:

*They used valves or vacuum tubes as their main electronic component.

*They were large in size, slow in processing and had less storage capacity.

*They consumed lot of electricity and produced lots of heat.

*They were not so accurate and reliable.

*They were very expensive.

E.g. ENIVAC, UNIVAC, IBM 650, etc.

Second generation computer (1957-1964)

The computer using transistors as a memory unit are known as second generation computer. A transistor could do the work of 1000 vacuum tubes.

Features:

*Transistors were used instead of vacuum tube.

*Processing speed is faster than first generation computers.

*Smaller in size.

*The input and output devices were faster.

*They are more reliable and faster then the first generation comuter.

e.g. IBM 1400 and 7000 series, control data 3600 etc.

Third generation computer (1965-1974)

The computer using ICs (integrated Chip) having capacity of the 300 transistors are known as third generation computers. They were smaller in size and had higher efficiency in speed and memory capacity. Very soon ICs were replaced by LSI ( large Scale Integrated), which consisted about 100 components. An IC containing about 100 components is called LSI.

Features:

*They used IC in place of the transistors.

*They were more accurate and reliable.

*LSI and VlSI were also developed.

*The mini computers were introduced in this generation.

e.g. IBM 360, IBM 370, etc.

Fourth generation computer (1975-1990)

the computers using VLSI containing more than 1000 components as a memory unit is known as fourth generation computers. The first micro processor 8008 was developed by American Company ( Intel cooperation) in 1971 and in 1974; another more power full microprocessor 8080 was developed. VLSI is also called as microprocessor.

Features:

*They used microprocessor as their main switching element.

*They are also called microprocessor or PC

*The size varies from desktop to laptop to palmtop

*They have very high speed of processing; they are 100% accurate, reliable, diligent and versatile.

*They have very large storage capacity.

e.g. IBM PC, Apple- Macintosh etc.

Fifth generation computer (1990-present and future)

The fifth generation computers are under development stage. These computers are being made using microprocessor and will use USLI (Ultra Large Scale Integration) chips. In the futures, such computers will use intelligent programming and improved human machine interfaces. It is estimated that these computers of fifth generation will have an Artificial Intelligence (AI) with a little thinking capacity and they will understand the natural language like English, Japanese, etc.

Features:

*They are the future computers which will use parallel processor or genetically engineered bio-chips *as their main switching element.

*They will have AI and will be able to understand natural language.

*They will have extremely high efficiency and reliability.