Best Ranked Colleges in USA

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1st GENERATION COMPUTER (1945 -1955)

          The development of electronic computers had clearly helped to visualize the concept of computer. The computer system has teken a big leap forward with each technological breakthrough during the development process. The functions performed by the computers and speed of their operations have been changing. There have been a great variation in size and cost of the computers.

Technological breakthrough in hardware and software resulted into more and more advanced computer system belonging to one particular technological class (or trend) is said to belong to a particular computer generation.

FIRST GENERATION COMPUTER ( 1945 - 1955)

          First generation computer used vacuum tubes as memory devices. The computers were large size and very costly and used the assembly language for programming.

• Colossus  was  the first  electronic  computer  of  this  era.  It's  every  aspect  was  kept secret by British Government.
• In 1945,  Von  Neumann  Architecture was introduced. Eckert and Mauchley began working  on  EDVAC  (Electronic  Discrete Variable Automatic  Computer)  but  it  never completed. Later Von Neumann developed his own EDVAC (IAS machine).
• In 1946, the development of ENIAC (Electronic Numerical Integrator and Computer), which was started in 1943, was completed.
• Some other  computers of this generation are  UNIVAC,  MARK  II,  MARK  III,  Z2, Z4, SSEC (Selective Sequence Electronic calculator) and some IBM computers series such as IBM 604, IBM 650, IBM 701, IBM 702.
• In 1954, first version of FORTRAN (Formula Translator) was published by IBM.

2nd & 3rd - GENERATION COMPUTER (1955 - 1965 - 1974)

Second Generation: Transistors and Batch System (1955 - 1965)           Second generation computers used transistors as CPU components and ferrite cores for main memory and magnetic disk drum/tapes as secondary memory. Some  high  level  languages  introduced  in  this  generation  are  FORTRAN,  ALGOL, BASIC and COBOL. Transistors increased the processing power of computer and decreased the size, cost and power usage as well. Thus, vacuum tubes computers were obsolete. Some  of  the  computers  in  this  generation  are  TX-0  (Transistorized  experimental Computer),  TX-2,  NEAC   1101  (from  NEC),  PDP   series  computers  from  Digital Company, IBM series computers such as IBM 709, IBM 1400 series etc               CDC (Control  Data  Corporation)  built fast computers called supercomputers  -  CDC 6600.  Third Generation: Integrated Circuits and Multiprogramming (1965 - 1980) The invention of silicon ICs (Integrated Circuits) allowed dozens of transistors to be put on a single chip. They used magnetic disks as memory devices but later they were replaced by semiconductor memories. Some of the major achievements are:

Multiprogramming was introduced. The computers were more powerful and smaller than previous generations. OSes like UNIX OS, system /360 OS, IBM MVS, BSD was developed. Some of the programming languages built in this generation are: ada, PASCAL, BCPL, SHRDLU, FORTRAN 66 and 77, SEQUEL (nowadays SQL) Intel introduced its microprocessors - Intel 4004, Intel 8080, 8086, 8088. Examples  of  third  generation  of  computer are  Apple  computers,  CDC's  Cyber-  175 and PDC series, STAR 1100 etc.