Transistors replaced vacuum tubes and ushered in the second generation of computers. The transistor was invented in 1947 but did not see widespread use in computers until the late 1950s. The
COMPUTER GENERATIONS timeline
generation of computers
Generation of Computer
2nd Generation 1959-64 Computers and Our Society
IBM 1400 series - Wikipedia
The history behind the generation wise evolution of the computers
Second Generation Computers (1956-1963)
Electronic Components as per Computer Generations – Robocraze
CLASSIFICATIONS OF COMPUTERS : #1 — Steemit