Ans :  the first generation computer developer in 1943-1953. the computer of this generation ere being model with electronic value and vacuum tube the first generation computer had some limitation , like they were of slow operation speed , limited programming capabilities limited computing facilities , short life pan high power consumption quit big in size huge setting up expenses etc.

        The computer of this generation are following 

  1. The electronic numerical integration and calculator ENIAC
          approx. period : in 1943-1946 in US

         Built by : A group of scientist headed by J. presper Kckert and John mulchy of Moore school of Engineering, University of Pennsylvania, UCA .

        Main Feature : it was the first all electronic computer.

                It used about 1800 vacuum tubes. It look up wall space in a 20x40 square feet room. It could add two numbers in 200 microseconds and multiply them in 2000 microsecond. It was used to solve ballistic problem. 

    2.     The Electronic Discrete Variable Automatic Computer                     EDVAC

            Approx. Period : In 1946-1952

            Built By : John Von Neumann    

            Main Features :  It was the first generation based on stored program concept. It could also stone both instruction and data in binary form instead of decimal numbers or humman readable words.    

3.     The Electronic Delay Storage Automatics Calculator EDSAC

          Approx Period: In 197-1949

        Built By : A group of scientists headed by Maurice Wilkes of Cambridge university Mathematical Laboratory.

        Main Feature: It could add two numbers in 1500 microseconds and multiply them in 4000 microseconds.

4.     The University Automatics Computer one UNIVAC 1

        Approx Period : In 1951

        Built By; UNIVAC Corporation.

        Main Features : It was the first digital computer that was not" one of a kind ". Its first installation was in the Census Bureau, which was used for 10 years. Its first business use was by General Electronic Corporation 1954. It marked the arrival of commercially available digital computers for business and scientific application.

5. IBM-701 

    Approx Period : 1952

    Built By : International Business Machines IbM Corporation.

    Main Feature : It was another commercially available digital computer for business and scientific application.

6. IBM : -650

    Approx. Period :  IN 1953    

    Built By : International Business Machines IBM Corporation.

    Main Feature : It was  an improved model of IBM-700 series machines. Its more than 1000 units were sold for use in business and scientific application.



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