Friday, 4 September 2015

GENERATIONS OF COMPUTER SYSTEM




Generations of Computer 




Some Facts:-


  1. Abacus known as earliest calculating device, used to add or subtract by adding and replacing the beads from the racks.
  2. Blaise Pascal invented the first mechanical adding Machine in 1942.
  3. Charles Babbage had designed “Difference Engine” in 1822, which can able to perform some arithmetic calculations but have prone to errors.
  4. In 1842, he designed, an analytical engine, which can able to perform full arithmetic function, but it could not be articulated due to reasons.
  5. But whatever principles he had laid down, are now being used as fundamental principles for designing the digital computers.



EDVAC:- Electronic discrete variable automatic computer.


ENIAC:- Electronic Numerical Integrator And Computer.


UNIVAC:- Universal Automatic Computer




GENERATION OF COMPUTER 


GENERATION MEANS THE TECHNOLOGICAL EVOLUTION OVER PERIOD OF TIME. THERE ARE 4 GENERATIONS:-





FIRST GENERATION:  (1942-1955)


  • IN THIS GENERATION VACUUM TUBES WERE USED TO STORE AND PROCESS THE DATA IN THE COMPUTER.
  • THESE VACUUM TUBES WERE MADE UP OF BREAKABLE GLASS THAT COULD CONTROL AND AMPLIFY ELECTRONIC SIGNALS.
  • EXAMPLES:- ENIAC AND EDVAC
  • DISADVANTAGE: - BULKY, PRODUCING LOTS OF HEAT(DUE TO VACUUM TUBE), UNRELIABLE RESULTS, FREQUENT HARDWARE FAILURE.
  • ADVANTAGE: - FAST AT THAT TIME.




SECOND GENERATION: (1955-1964)


  • TRANSISTORS WERE USED.
  • THESE TRANSISTORS WERE SMALL COMPONENTS, WHICH WERE ASSEMBLED TO FULL FUNCTIONAL CIRCUIT.
  • THIS TECHNOLOGY HAD REDUCED THE SIZE OF THE COMPUTER.
  • ADVANTAGES:-LESS PRONE TO HARDWARE FAILURE,FASTER THAN FIRST GENERATION.
  • DISADVANTAGES:- REQUIRE AIR-CONDITION, FREQUENT MAINTENANCE.


THIRD GENERATION: (1964-1975)


  • INTEGRATED CIRCUIT WAS USED IN THIS GENERATION.
  • THESE ICs HAVE LARGE NUMBER OF VERY TINY INTEGRATED CIRCUITS MADE UP OF SILICON KNOW AS SILICON CHIP.
  • THIS TECHOLOGY REDUCED THE SIZE OF COMPUTER DRAMATICALLY.
  • ADVANTAGES: MORE RELIABLE,GENERATED LESS HEAT,FAST, COST EFFECTIVE AND PORTABLE THAN THE PREVIOUS GENERATION COMPUTERS.
  • IT WAS USED FOR GENERAL PURPOSE AND CONSUMED LESS POWER.
  • DISADVANTAGES:-REQUIRE AIR-CONDITIONAND THE TECHNOLOGY WAS VERY SOPHISTICATED.


FOURTH GENERATION: (1975- to Present)


  • ICs ARE USED.
  • ICs IS KNOWN AS SSI (SMALL SCALE INTEGRATION), IT CONTAINED VERY LESS NUMBER OF COMPONENTS.
  • LATERON IT WAS POSSIBLE TO INTEGRATE MORE 100 COMPONENTS ON A SINGLE UNIT, THESE ICs WERE KNOWN AS MSI (MEDIUM SCALE INTEGRATION)
  • AFTERTHAT, LSI(LARGE SCALE INTEGRATION) WAS DEVELOPED WHICH HAVE MORE THAN THOUSAND OF COMPONENTS INTEGRATED.
  • LATERON VLSI (VERY LARGE SCALE INTEGRATION) IS BEING DEVELOPED WHICH WILL HAVE MORE THAN MILLION CIRCUIT COMPONENTS INTEGRATED ON IT.
  • LATERON, SOC (SYSTEM ON CHIP) IS BEING DEVELOPED WHERE THE ENTIRE COMPONATS OF A SYSTEM ARE INTEGRATED.
  • WITH THIS TECHNOLOGY, WE COULD ABLE TO DEVELOP SMART PHONE / TABLETS WHICH IS CAPABLE OF REPLACING LAPTOP.
  • THIS TECHNOLOGY MADE COMPUTERS VERY COMPACT AND VERY FAST.
  • ADVANTAGES:-VERY  RELIABLE, HEAT GENERATION IS INSIGNIFICANT, NO AIR CONDITIONER REQUIRED,ECONOMICAL TO PRODUCE IN LARGE SCALE, NEGLIGENCE HARDWARE FAILURE.
  • DISADVANTAGE:- HIGHLY SOPHISTICATED.