Generations of Computers

Generations of Computers

“Generation”    in  computer   talk  is  a  step  in technology.   It  provides   a  framework   for  the  growth  of  computer industry,  Originally,  the term  “generation”   was used to distinguish   between  varying  hardware  technologies   but it has now been extended  to include  both hardware  and software  that together  make up a computer  system.

I. First Generation (1940-56)

Introduction of the INOVAC I in 1951 marked the beginning of the first generation. General features of these computers were:

i. These computers were based on vacuum tube technology.

ii. Punched cards used for feeding information.

iii. Punched cards and paper used for getting results.

iv. Magnetic tapes were used for external storage.

v. Entire machine is dedicated to a particular job until completed.

vi. Computation time was milliseconds.

vii. Since thousands of vacuum tubes were used, they generated a large amount of heat. Therefore, air conditioning was essential.

viii. These were non portable and very slow machine.

ix. Development of machine language and assembly language. Machine language uses 0s  (zero) and 1s for coding of the instructions.

x. Typical computers used were: UNVAC I, EDVAC, UNIVAC, IBM 650, BURROUGHS 220.

II. Second Generation (1956-1963)

i. John Bardeen, William Shockley,  and Walter  Brattain  invented  a new electronic  switching  device  called transistor  at Bell Laboratories   in These transistors formed the basis for the second generation of computers.

ii. The computers now were much faster, more reliable and more versatile than first generation computers.

iii. Smaller as computers to first generation computers.

iv. The computational time reduced to microseconds from milliseconds.

v. These were more reliable and less prone to hardware failure. Thus less frequent maintenance required.

vi. These were more portable and generated less amount of heat but still required air conditioning.

vii. Assembly language was used to program computers. Assembly language uses mnemonics like ADD for addition and SUB for subtraction for coding o instructions. It is easier to write in assembly language than machine language. High level programming languages such as versions of BASIC, PL/1, COBOL and FORTAN were also developed during this period.

viii. Manual assembly of components still required.

ix. Typical computer used were : IBM 1400 Series and 7000 Series, Control Data 3600, General Electric 635 and Honeywell 200, CDC 1604 and PDP-8.

III. Third Generation ( 1964 – 1971)

i. In 1958, Jack Clair  Kilby  and  Robert Noyce    invented  the  first  integrated   The third generation computers used the Integrated Circuit (IC) chips. In IC chips, multiple transistors are placed on a silicon chip. Silicon is a type of semiconductor. The use o these chips increased efficiency of computer, manifold.

ii. The keyboard and monitor were used to interact with the third generation computer instead of punched card and printouts.

iii. Magnetic disks used for external storage.

iv. They were smaller than second-generation  computers  requiring  smaller

v. They  were  more  reliable   and  less  prone  to  hardware   failures   than   second-generation    computers requiring  lower maintenance

vi. They  consumed    less   power   and   dissipated    less   heat   than   second-generation         The rooms/areas    in  which   third-generation    computers   were   located   still  required   to  be  properly   air- conditioned.

vii. High level languages were used extensively for programming, instead of machine language and assembly language. High level language including RPG (Report Program Generator) and PASCAL were developed. Heavy emphasis was laid on applications oriented languages -FORTAN and COBOL.

viii. The computation time was in nanoseconds.

ix. Typical computers used were: NCR 395, B6500, IBM/360,IBM 370, PDP 11.

IV. Fourth Generation (1971 – Till date)

i. The forth generation computers led to an era of Large Scale Integration (LSI) and very Very Large Scale Integration (LSI) technology.

ii. This generation of computer gave rise to personal computers.

iii. Several new operating systems like the MS-DOS and MS-Windows developed during this type. This generation of computer supported Graphic User Interface (GUI).

iv. The computation time is in picoseconds.

v. The Intel 4004 chip was the first microprocessor. In 1981, IBM introduced the first computer for home use In 1984, Apple introduced the Macintosh.

vi. Typical computers used : IBM system/370, Burroughs B7700 and HP 3000.

IV. Fifth Generation (Present – Beyond)

i. Use Super Large Scale Integrated (SLSI) chips that are able to store millions of components on a single chip.

ii.  Uses parallel processing that allows several instructions to be executed in parallel, instead of serial execution. The Intel dual core microprocessor uses parallel processing.

iii.  The fifth generation computers are based on Artificial Intelligence (AI). Artificial Intelligence includes areas like Expert System (ES) , Natural Language Processing (NLP) , speech recognition, voice recognition, robotic, etc.

iv.  They have faster and larger primary and secondary storage as compared  to their

v.  Newer and more  powerful  applications,   including  multimedia   applications,   make  the  systems  more useful  in every occupation.

Mankind has entered  the information  age from an industrial  age that prevailed  till a few years ago. This change is expected to have a profound  effect on the way we live, make money and deal with wars. It would therefore be useful to examine the nature of information  and the information  technology  that is at the root of future  opportunities,   challenges  and competition.  Information  has been there since beginning. Information  technology  was also there. But it is computer,  which  has made  information technology so popular.