MOS (operating system)

MOS signifies 'Mobile Operating System' (Russian: Моби́льная Операцио́нная Систе́ма, МОС). It was a Soviet clone of Unix in the 1980s.  This operating system was commonly found on SM EVM minicomputers; it was also ported to ES EVM and Elbrus. MOS was also used in high-end PDP-11 clones.

There have been several modifications of MOS named MNOS, DEMOS, INMOS etc.

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