Page "Mainframe computer" Paragraph 18

Several manufacturers produced mainframe computers from the late 1950s through the 1970s.

The group of manufacturers was first known as " IBM and the Seven Dwarfs ": IBM, Burroughs, UNIVAC, NCR, Control Data, Honeywell, General Electric and RCA.

Later, shrinking, it was referred to as IBM and the BUNCH.

IBM's dominance grew out of their 700 / 7000 series and, later, the development of the 360 series mainframes.

The latter architecture has continued to evolve into their current zSeries mainframes which, along with the then Burroughs and Sperry ( now Unisys ) MCP-based and OS1100 mainframes, are among the few mainframe architectures still extant that can trace their roots to this early period.

That said, while IBM's zSeries can still run 24-bit System / 360 code, the 64-bit zSeries and System z9 CMOS servers have nothing physically in common with the older systems.

Notable manufacturers outside the USA were Siemens and Telefunken in Germany, ICL in the United Kingdom, Olivetti in Italy, and Fujitsu, Hitachi, Oki, and NEC in Japan.

The Soviet Union and Warsaw Pact countries manufactured close copies of IBM mainframes during the Cold War ; the BESM series and Strela are examples of an independently designed Soviet computer.