computer generation

Any of the five broad groups into which computers may be classified chronologically: first generation, the earliest computers, developed in the 1940s and 1950s, made from valves and wire circuits; second generation from the late 1950s to the early 1960s, based on transistors and printed circuits; third generation from the early 1960s to 1970, using integrated circuits and often sold as families of computers, such as the IBM 360 series; and fourth generation, from the 1970s and currently still in use, using microprocessors, large-scale and very large-scale integration (LSI and VLSI), and sophisticated programming languages.