The History of the Silicon Based Desktop Computer

Timeline of Four Generations of Development towards today's Desktop Computers

Before and 1925 to 1945
Prior to First Generation
Cross-sectional view of a field-effect transistor (F.E.T.), showing source, gate and drain terminals

Cross-sectional view of a field-effect transistor (F.E.T.), showing source, gate and drain terminals

1946 to 1959
1st Generation
BJT (Bipolar Juntion Transistor) NPN schematic symbol, where An NPN transistor comprises two semiconductor junctions that share a thin p-doped regionBJT (Bipolar Juntion Transistor) NPN schematic symbol, where a PNP transistor comprises two semiconductor junctions that share a thin n-doped region. N-type means doped with impurities that provide mobile electrons, while P-type means doped with impurities that provide holes that readily accept electrons.

BJTs (Bipolar Juntion Transistors) NPN and PNP schematic symbols, where An NPN transistor comprises two semiconductor junctions that share a thin p-doped region, and a PNP transistor comprises two semiconductor junctions that share a thin n-doped region. N-type means doped with impurities that provide mobile electrons, while P-type means doped with impurities that provide holes that readily accept electrons.

1959 to 1965
2nd Generation
MOSFET, showing gate (G), body (B), source (S) and drain (D) terminals. The gate is separated from the body by an insulating layer (pink).

MOSFET, showing gate (G), body (B), source (S) and drain (D) terminals. The gate is separated from the body by an insulating layer (pink).

1965 to 1971
3rd Generation
Integrated Circuits: Erasable programmable read-only memory (EPROM) integrated circuits in dual in-line packages. These packages have a transparent window that shows the die inside. The window is used to erase the memory by exposing the chip to ultraviolet light.

Integrated Circuits: Erasable programmable read-only memory (EPROM) integrated circuits in dual in-line packages. These packages have a transparent window that shows the die inside. The window is used to erase the memory by exposing the chip to ultraviolet light.

1971 to 1980 and on to Present
4th Generation
Intel 4004 Microprocessor in 1971 (year)

Intel 4004 Microprocessor in 1971 (year)