First Generation Computers: The first electronic digital computer was designed and built in 1937 and was know as the ABC Computer. This system was followed by the first large-scale electronic, general-purpose digital computer (EN IAC) in 1946. These early computers used vacuum tubes technology and were quite bulky in terms of their weight, floor space required and their electrical consumption. Second Generation Computers: The transistor, an internal component of the computer system was invented in 1947 and would eventual replace the Vacuum Tube technology of the older systems in 1958 to mark the introduction of the 2 nd generation.

This new technology proved to be more reliable and was less bulky. In 1951 the first commercially available electronic computer, the Univ ac 1 was introduced. Public awareness of computers increases as a result of this system being used to analysed only 5% of the population and correctly predicting a presidential election. IBM introduces a Model 650 in 1953 and had planned to manufacture only 50 units, but was forced to produce in excess of 1000 systems.

Later that year IBM introduced the 700 series of machines and went on to dominate the mainframe market for the next decade. This era saw improvements in the storage capacity of computers as well as the introduction of the first external magnetic storage disk. Third Generation Computers: This generation was introduced in 1964 had their controlling circuitry stored on chips. With this introduction came the compatible systems, which was a merger of the business and scientific lines. Developments continued to grow and we saw the introduction of the first mini-computer in 1965. Fourth Generation Computers: The fourth generation was introduced in 1970 and used technology that had improved on the chips used in the 3 rd generation.

These chips were now made up of as many as 15, 000 circuits up from the previous 1, 000 maximum. The development of technologies continued to grow with marked improvements in the development of the chip. These microprocessors as they became known developed from the 286 in 1984 through the 386 in 1986 and on to the 486 processor in 1989. The 486 processor had over a million transistors and was four times as fast as the 386 processor before it.