A Brief History of Computing
- The various eras that the history of computer has passed through

© Copyright 1996-2005, Stephen White

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1943 Computers between 1943 and 1959 (or thereabouts - some say this era did not start until UNIVAC-1 in 1951) usually regarded as 'first generation' and are based on valves and wire circuits. The are characterised by the use of punched cards and vacuum valves. All programming was done in machine code. A typical machine of the era was UNIVAC, see 1951.
1953 Estimate that there are 100 computers in the world.
1959 Computers built between 1959 and 1964 are often regarded as 'Second Generation' computers, based on transistors and printed circuits - resulting in much smaller computers. More powerful, the second generation of computers could handle interpreters such as FORTRAN (for science) or COBOL (for business), that accepting English-like commands, and so were much more flexible in their applications.
1964 Computers built between 1964 and 1972 are often regarded as 'Third Generation' computers, they are based on the first integrated circuits - creating even smaller machines. Typical of such machines was the IBM 360 series mainframe, while smaller minicomputers began to open up computing to smaller businesses.
1972 Computers built after 1972 are often called 'fourth generation' computers, based on LSI (Large Scale Integration) of circuits (such as microprocessors) - typically 500 or more components on a chip. Later developments include VLSI (Very Large Scale Integration) of integrated circuits 5 years later - typically 10,000 components. Modern circuits may now contain millions of components. This has led to very small, yet incredibly powerful computers. The fourth generation is generally viewed as running right up until the present, since although computing power has increased the basic technology has remained virtually the same. By the late 1990s many people began to suspect that this technology was reaching its limit, further miniaturisation could only achieve so much. 64 megabit RAM chips have circuitry so small that it can be measured in atoms, circuits this small pose many technical problems - notably the heat created but they are also very susceptible to influence by temperature or radiation. It has been argued fifth generation computers are based on parallel processing and VLSI integration - but are still being developed and I'd be wary of writing the history books until the history has actually occured! Besides computers need to be massively parallel before they give a significant enough advantage to warrent a new generation of computing.

© Copyright 1996-2004, Stephen White My homepage - email:swhite@ox.compsoc.net