Generations of Computer

• 1^st To 4^th Generation Computers and Major Features of each Generation of Computers

Computer Generation	Year	Switching Device	Storage Device	Speed	Operating System	Language	Application
First*	1949-54	Vacuum Tubes/ Electronic Valves	Acoustic delay lines and later magnetic drum, 1KB memory,	333 micro seconds	Mainly batch	Machine and assembly languages, Simple monitors	Mostly scientific later simple business systems
Second**	1954-64	Transistors	Magnetic core, main memory, tape and disk peripheral memory, 100 KB main memory	10 micro seconds	Multi-bag remaining, Time sharing	High level languages, Fortran, Cobol, Algol, Batch, Operating system.	Extensive business applications, Engineering desing optimization scientific research
Third***	1964-80	Integrated Circuits	High speed magnetic corer Large disks 100 MB, 1MB main	100 nano seconds	Real time, Time sharing	Fortran IV, Cobol 68 PI/I, Time sharing Operating system,	Database management system online systems Personal
Fourth***	1980-till now	Large scale integrated circuits. Microprocessors (LSI)	Semi-conductor memory, Winchester disk, 10 MB main memory, 1000 MB disks	300 nano seconds	Time sharing, networks	Fortran 77, Pascal, ADA, Cobol-74	computers, Distributed systems Integrated CAD/CAM Real time control, Graphic oriented systems

5th Generation (From Present Days to Future)

These computers are yet to come into the market and are being developed by scientists and researchers.

·     First Generation computers : The computers built during World War II are known as the 1^st Generation computers.  These were specific task oriented and extremely difficult to programme.  These computers relied on vacuum tubes and magnetic drums.    In 1943 was built ENIAC (Electronic Numerical Integrator Analyzer and Computer and it consisted of 18000 vacuum tubes and 70,000 resistors etc.   In 1945 was developed EDVAC (Electronic Discrete Variable Automatic Computer).   In 1951 came the Universal Automatic computer (UNIVAC I), designed by Remington Rand .

 

·     2^nd Generation Computers :  In this generation vacuum tubes were replaced by transistors and initially these were made to meet the requirements of atomic energy laboratories.  High level languages such as COBOL (Common Business Oriented Language) and FORTRAN (Formula Translator) were used.  Some of these are still used.

 

·   3^rd Generation : In this age, transistors (which used to generate lot of heat and damaged the sensitive areas of computers) were replaced with Integrated Circuits (IC).

 

·      4^th Generation : These are modern day computers.  The size of computers has drastically gone down.  Very Large Scale (VLSI) and Ultra Large Scale (ULSI) made it possible that millions of components could be fit into a small chip.  The Intel 4004 chip was developed in 1971 and all the components of computer (CPU, memory and input and output controls) were located on a minuscule chip.   In 1981, IBM introduced Personal Computer for home and office use.     Slowly, it came down from Desktop to Laptops and then to Palmtops.  Then came GUI (Graphic User Interface) in which instead of typing the instructions, user merely used Mouse and clicks to instruct computers to do the job