Abacus was the first manual calculating device,invented in Asia many centuries ago.In 1617,John Napier,a Scottish mathematician invented a mechanical calculator called the Napier's bones.In 1822 Charles Babbage, an English mathematician, Difference Engine to compute tables of numbers for naval navigation.In the year 1834,digital computer,called Analytical Engine by Babbage.The analytical engine had all the parts of a modern computer,it had four components the store,the mill,the punched card reader and printed output.Herman Hollerith-Tabulating Machine for 1880 US census.In 1994,Howard A Eiken invented first American general purpose electro mechanical computer called Mark 1 and later on its Successor,Mark 2.

Father of computer is Charles Babbage,Father of computer science is Alan Turing, Father of super computer is Seymour cray,Father of Compact Disc is James T Russell,Father of Floppy Disc is Alan Shugart,Father of mouse is Douglas Engelbert,Father of e-Mail is Ray Tomlinson, Father of Indian Super Computer is Vijay P Bhatkar,Father of IT in India is Rajiv Gandhi,Father of internet is Vinton cerf,Father of free software is Richard Stallman,Father of world wide web is Tim Berners Lee,Basic Architecture of Computer,John von Neumann,First programmer is Lady Ada Lovelae ,First Electronic Computer is ENIAC,founders are J.P.Eckert and J.W.Mauchly,First computer for the home user introduced IBM in 1981.

           First generation computers marked by the use of  Vaccum tubes or valves,relied on Machine language.They were very large in size.consumed too much power and generated too much heat.They were very unreliable and broke down frequently and required regular maintenance.ENIAC(Electronic Numerical Integrator and Calculator),First electronic computer 1946 by John Mauchly and J.Presper Eckert of the University of Pennsylvania,US EDSAC(Electronic Delay Storage Automatic Calculator),first stored program computer.1949 by Maurice Wilkes.UNIVAC is the first commercial Computer for the US Census Burea in 1951 by John Mauchly and J presper Eckert .IAS Machine,(Princeton's Institute of Advanced Studies) new  version of the EDVAC,built by von Neumann,1952.In 1954,the philco corporation developed transistors.Marked by the use of transistors which were made from pieces of silicon.Assembly language and High level programming languages like FORTRAN,COBOL were  used.Used batch processing and multiprogramming operation system.Smaller in size and less heat generated than first generation computers.Faster and more reliable than earlier computers.Limited storage capacity,consumed more power and we're also relatively slow to performance also required regular maintenance.Then the use of Integrated circuits in place of transistors.Integrated circuits or chip discovered in 1964 ,a number of transistors could be  sealed up into a tiny package.Maller in size which generated less heat and required very less power as compared to earlier two generations.Which are faster and more reliable.Less storage capacity, relatively slower performance,became out dated around the year 1978 whenit was found that thousands of ICs could be integrated onto a single chip, called LSI(Large Scale Integration).