OS/VS

OS/VS may refer to one of a number of IBM operating systems for System/370 and successors characterized by the use of virtual storage (VS):

IBM OS/VS1, successor to MFT II, 1972-1984
IBM OS/VS2, successor to MVT, including:
- OS/VS2 version 1, also known as SVS (Single Virtual Storage), 1972-1974
- OS/VS2 version 2, also known as MVS (Multiple Virtual Storage), 1974-1981

OS/VS1 had no follow-on systems. Successor operating systems of OS/VS2 dropped the "OS/VS" tag and became simply "MVS/SE", "MVS/SP", "MVS/XA", etc.

History of IBM mainframe operating systems
Early mainframe computer OSs GM OS & GM-NAA I/O (1955) BESYS (1957) UMES (1958) SOS (1959) IBSYS (1960) CTSS (1961)
Miscellaneous S/360 line OSes BOS/360 (1965) TOS/360 (1965) TSS/360 (1967) MTS (1967) ORVYL (1967) MUSIC (1972) MUSIC/SP (1985)
DOS/360 and successors (1966) DOS/VS (1972) DOS/VSE (1979) VSE/SP (1983, 1985) VSE/ESA (1991) z/VSE (2005)
OS/360 and successors (1966) MFT (1966) MFT II (1968) OS/VS1 (1972) OS/VS1 BPE MVT (1967) 65MP OS/VS2R1 (SVS) (1972) MVS (OS/VS2R2 and later) (1974) MVS/SE (1978) MVS/SE 2 (1979) MVS/SP Version 1 (1980) MVS/XA (1983) MVS/ESA (1988) OS/390 (1995) z/OS (2000)
VM line CP-40 /CMS (1967) CP-67 /CMS (1967) VP/CSS (1968) VM/370 (1972) VM/BSE (BSEPP) VM/SE (SEPP) VM/SP (1980) VM/XA MA (1984) VM/XA SF (1985) VM/XA SP (1988) VM/ESA (1990) z/VM (2000)
TPF line ACP (1967) TPF (1979) z/TPF (2005)
UNIX and Unix-like UTS (1981) AIX/370 (1990) AIX/ESA (1991) MVS/ESA OpenEdition (1993) OS/390 UNIX System Services (1996) Linux (1999) z/OS UNIX System Services (2001) OpenSolaris (2008)

See also