Generation of Computers By aitanalp Period: 1946 to 1959 First Generation Vacuum tube based Period: 1959 to 1965 Second Generation Transistor based Period: 1965 to 1971 Third Generation Integrated Circuit based Period: 1971 to 1980 Fourth Generation VLSI microprocessor based Period: 1980 to 2021 Fifth Generation ULSI microprocessor based