Computer. By Maryanne Sita Period: Mar 19, 1940 to Mar 19, 1950 first generation of computers. the first generation of computers. Period: Mar 12, 1956 to Mar 12, 1963 Second generation of computers Second generation of computers. Period: Mar 12, 1964 to Mar 12, 1971 Third generation of computers. Third generation of computers Period: Mar 12, 1971 to Mar 12, 2013 fourth generation of computers from 1971 to present. Period: Mar 12, 2013 to Mar 12, 2030 fifth generation of computers from the present onwards.