First Generation

FIRST GENERATION (1942 –1955) The first generation computer is made up of vacuum tube.A vacuum tube was a fragile glass device which used filaments which controls and amplify electronic signals.These computer helps in computations in limmisaconds. Characteristics: 1) They are bulky in size and required large rooms for installation. 2) The vacuum tubes emits large amount of heat and easily burnt out. 3) They consumes large amount of power. 4) Vacuum tubes have filament and hence they do not last long. 5) These computers are prone to frequent hardware failures. SECOND GENERATION 1)These computers are made of an electronic switching device called transistor. 2)The transistors are made of germanium semiconductor and easier to handle. 3)They are much faster to operate. 4)They consumes much less power consumed by tube. 5)They are smaller in size. 6)They are less expensive. 7)They dissipates less heat as compared to vacuum tube. 8) They are more reliable and less prone to hardware failures. THIRD GENERATION Integrated circuits ( IC) consists of several electronic components like transistors,capacitors and resistors. Grown on a single chip of silicon. The IC technology was named small scale integration(SSI) which contains only about 20 electronic components and later it was named medium scale integration(MSI).

Characteristics: 1)They were more powerful than the second generation computers. 2)They are smaller in size. 3)they disspates less heat. 4)They consumes less power. 5)They are more reliable and less prone to hardware failures. 6)They have timesharing operating system. FOURTH GENERATION Large scale integration(LSI) when it was possible to integrate over 30,000 electronic components on a single chip followed by very large scale integration(VLSI) when it was possible to integrate about one million electronic components. This lead to the development of microprocessor.A microprocessor consists all the circuits needed to perform arithmetic logic operation and control functions, the core activities of computers on a single chip. Characteristics: 1) The PCs were smaller and cheaper . 2) No airconditioning is required they can be kept at room temperature. 3) They consumes less power. 4) They consume less power ,reliable and faster than the third generation computers. 5) They were general purpose machines. 6) GUI(Graphical user interface) enables new users to quickly learn how to use computers. 7) They have both software and hardware feature which are handled by the users according to their needs. 8) The PCs of the fourth generation made computers affordable even by individuals. FIFTH GENERATION Further miniature of electronic components caused the dramatic increase in the power of the microprocessor chips.

The VLSI technology became ULSI(Ultra Large Scale Technology) technology in the fifth generation resulting in the production of microprocessor chip. Characteristics: 1)Portable PC (notebook computer) are much more smaller and handy than the PC s of the fourth generation. 2) The user can use them even while traveling. 3)They consumes less power than fourth generation computers. 4) They are more reliable and less prone to hardware failures. 5)More user friendly interfaces with multimedia applications make the systems more useful and easier to use by everybody. 6)They have both software and hardware features.