First-generation computer  (1946-1959)

The early first-generation laptop was powered by thousand of vacuum tubes. Vacuum tubes were the sole electronic element out there throughout those days.

Vacuum tube emitted an outsized quantity of warmth thanks to that there have been frequent forcefulness outs.

Therefore, constant maintenance and correct air-con were needed.

The first trendy information processing system ENIAC(Electronic Numerical measuring instrument and Calculator) in 1946. it had been developed by John Mauchly and Eckart within the USA. It occupied an area measurement nine-meter X fifteen meter and contained eighteen,000 vacuum tubes and weighed thirty tons.

Features of 1st generation computer:-

    • Vacuum tube technology.
    • Speed in milliseconds.
    • Machine and programming language programming.
    • The quickest computer of their time.
    • Punched card for input.
    • Magnetic tape and magnetic drum for secondary storage.
    Drawbacks of 1st generation computer:-
    • The terribly massive size and occupied a great deal of house.
    • Consumed a great deal of power.
    • Heat generation was quite high.
    • Poor responsibility thanks to the electronic device.
    • These computers had restricted business use as a result of they were troublesome to program.
    • Non-portable.
    • Continuous maintenance needed.

    EXAMPLE:- UNIVAC I, UNIVAC II, IBM650, etc.

    Second-generation computer(1959-1965)

    In this generation, the semiconductor unit replaced vacuum tubes, as a result, the physical size of the pc was greatly reduced.
    semiconductor unit may be a little electrically operated switch which will alternate between 'on' and 'off' immeasurable times per second.

    IBM 1401 was an awfully well-liked second-generation laptop. algebraic language and programming language were the high-level languages used on these computers.


    Features of 2nd generation computer:-

    • Transistor-based technology.
    • Speed in microseconds.
    • High-level languages algebraic language and programming language were used.
    • In comparison to first-generation computers, they were straightforward to program and use, so they were used commercially.
    • Smaller, faster, and additional reliable than the primary generation computers.

    Drawbacks of 2nd generation computers:-

    • Frequent maintenance required.
    • Air conditioning needed.

     EXAMPLE:- IBM-1401, IBM-1620, etc.

    THIRD GENERATION COMPUTERS(1965-1971)

      In this generation, transistors were replaced by integrated circuits (ICs). associate degree IC may be a semiconductor or wafer that contains all components of electronic circuits {in a|during a|in an exceedingly|in a terribly} very tiny space. IBM 360 was an especially well-liked third-generation laptop. the multi sharing and execution conception of the software package was additionally introduced during this generation.

      Features of 3rd generation computers:-

      • Integrated circuit-based technology.
      • Speed in nanoseconds.
      • Used additional high-level languages, as well as RPG and Pascal.
      • Smaller, faster, and additional reliable than 2d generation computers.
      • Time-sharing and on line process potential.
      • Easily transportable

      The drawback of 3rd generation computers:-


      • Complex and complicated technology was needed for the production of the central processor and alternative elements.
      EXAMPLE:- IBM 360, PDP-8 series, etc.

      FOURTH GENERATION COMPUTERS (1971-1989) 

      The period of the fourth generation was from 1971-1980. Computers of fourth-generation used terribly massive Scale Integrated (VLSI) circuits. VLSI circuits having concerning 5000 transistors and alternative circuit components with their associated circuits on one chip created it potential to possess microcomputers of the fourth generation.
      Fourth-generation computers became additional powerful, compact, reliable, and cheap. As a result, it gave rise to the private laptop (PC) revolution. during this generation, time-sharing, period networks, distributed software packages were used. All the high-level languages like C, C++, DBASE, etc., were employed in this generation.


      Features of 4th generation computers:-


      • Large scale integration (LSI) technology.
      • Speed in nanoseconds.
      • Development of microprocessor-based technology.
      • Negligible heat generation.
      • Very reliable.
      • High storage capability.
      • Easily transportable as a result of the tiny size.
      • Hardwar failure was less. therefore, the upkeep price was negligible.

      The drawback of 4th generation computers:-

      • Complex and complicated technology was needed for producing the central processor and alternative elements.
      EXAMPLE:- HP 3000 minicomputers.