Timeline of operating systems
This article presents a timeline of events in the history of computer operating systems from 1951 to the current day. For a narrative explaining the overall developments, see the History of operating systems.

1950s
 1951
 LEO I 'Lyons Electronic Office' was the commercial development of EDSAC computing platform, supported by British firm J. Lyons and Co.
 1955
 MIT's Tape Director operating system made for UNIVAC 1103
 1955
 General Motors Operating System made for IBM 701
 1956
 GM-NAA I/O for IBM 704, based on General Motors Operating System
 1957
 Atlas Supervisor (Manchester University)  (Atlas computer project start)
 BESYS (Bell Labs), for IBM 704, later IBM 7090 and IBM 7094
 1958
 University of Michigan Executive System (UMES), for IBM 704, 709, and 7090
 1959
 SHARE Operating System (SOS), based on GM-NAA I/O

1960s
 1960
 IBSYS (IBM for its 7090 and 7094)
 1961
 CTSS demonstration (MIT's Compatible Time-Sharing System for the IBM 7094)
 MCP (Burroughs Master Control Program)
 1962
 Atlas Supervisor (Manchester University)  (Atlas computer commissioned)
 BBN Time-Sharing System
 GCOS (GE's General Comprehensive Operating System, originally GECOS, General Electric Comprehensive Operating Supervisor)
 1963
 AN/FSQ-32, another early time-sharing system begun
 CTSS becomes operational (MIT's Compatible Time-Sharing System for the IBM 7094)
 JOSS, an interactive time-shared system that did not distinguish between operating system and language
 Titan Supervisor, early time-sharing system begun
 1964
 KDF9 Timesharing Director (English Electric) – an early, fully hardware secured, fully pre-emptive process switching, multi-programming operating system for KDF9 (originally announced in 1960)
 Berkeley Timesharing System (for Scientific Data Systems' SDS 940)
 Dartmouth Time Sharing System (Dartmouth College's DTSS for GE computers)
 OS/360 (IBM's primary OS for its S/360 series) (announced)
 SCOPE (CDC 3000 series)
 PDP-6 Monitor (DEC) descendant renamed TOPS-10 in 1970
 EXEC 8 (UNIVAC)
 1965
 THE multiprogramming system (Technische Hogeschool Eindhoven) development
 Multics (MIT, GE, Bell Labs for the GE-645) (announced)
 BOS/360 (IBM's Basic Operating System)
 TOS/360 (IBM's Tape Operating System)
 TSOS (later VMOS) (RCA)
 Pick operating system
 1966
 OS/360 (IBM's primary OS for its S/360 series) PCP and MFT (shipped)
 DOS/360 (IBM's Disk Operating System)
 MS/8 (Richard F. Lary's DEC PDP-8 system)
 GEORGE 1 & 2 for ICT 1900 series
 SODA for Elwro's Odra 1204
 1967
 CP-40, predecessor to CP-67 on modified IBM System/360 Model 40
 CP-67 (IBM, also known as CP/CMS)
 Michigan Terminal System (MTS) (time-sharing system for the IBM S/360-67 and successors)
 ITS (MIT's Incompatible Timesharing System for the DEC PDP-6 and PDP-10)
 ORVYL (Stanford University's time-sharing system for the IBM S/360)
 TSS/360 (IBM's Time-sharing System for the S/360-67, never officially released, canceled in 1969 and again in 1971)
 OS/360 MVT
 WAITS (SAIL, Stanford Artificial Intelligence Laboratory, time-sharing system for DEC PDP-6 and PDP-10, later TOPS-10)
 1968
 Airline Control Program (ACP) (IBM)
 THE multiprogramming system (Eindhoven University of Technology) publication
 TSS/8 (DEC for the PDP-8)
 1969
 TENEX (Bolt, Beranek and Newman for DEC systems, later TOPS-20)
 Unics (later Unix) (AT&T, initially on DEC computers)
 RC 4000 Multiprogramming System (RC)
 Multics (MIT, GE, Bell Labs for the GE-645 and later the Honeywell 6180) (opened for paying customers in October)
 GEORGE 3 For ICL 1900 series

1970s
 1970
 DOS-11 (PDP-11)
 1971
 RSTS-11 2A-19 (First released version; PDP-11)
 OS/8
 1972
 Data General RDOS
 Edos
 Operating System/Virtual Storage 1 (OS/VS1)
 Operating System/Virtual Storage 2 R1 (OS/VS2 SVS)
 Virtual Machine Facility/370 (VM/370), sometimes known as VM/CMS
 Virtual Machine/Basic System Extensions Program Product (BSEPP or VM/SE)
 Virtual Machine/System Extensions Program Product (SEPP or VM/BSE)
 MUSIC/SP
 PRIMOS (written in FORTRAN IV, that didn't have pointers, while later versions, around version 18, written in a version of PL/I, called PL/P)
 1973
 Эльбрус-1 (Elbrus-1) – Soviet computer – created using high-level language uЭль-76 (AL-76/ALGOL 68)
 VME – implementation language S3 (ALGOL 68)
 RSX-11D
 RT-11
 Alto OS
 1974
CP/M
DOS-11 V09-20C (Last stable release, June 1974)
 Sintran III
 MONECS
 Multi-Programming Executive (MPE) – Hewlett-Packard
 Hydra – capability-based, multiprocessing OS kernel
 Operating System/Virtual Storage 2 R2 (MVS)
 1975
 BS2000 V2.0 (First released version)
 Version 6 Unix
 1976
 Cambridge CAP computer – all operating system procedures written in ALGOL 68C, with some closely associated protected procedures in BCPL
 Cray Operating System
 FLEX
 TOPS-20
 Tandem Nonstop OS v1
 1977
 1BSD
 KERNAL
 OASIS operating system
 TRSDOS
 Virtual Memory System (VMS) V1.0 (Initial commercial release, October 25)
 1978
 2BSD
 Apple DOS
 HDOS
 PTDOS
 TRIPOS
 UCSD p-System (First released version)
 Lisp machine (CADR)
 KVM/370 – security retro-fit of IBM VM/370
 KSOS – secure OS design from Ford Aerospace
 MVS/System Extensions (MVS/SE)
 1979
 3BSD
 Atari DOS
 POS
 NLTSS
 UNIX/32V
 Version 7 Unix
 UCLA Secure UNIX – an early secure UNIX OS based on security kernel
 MVS/System Extensions R2 (MVS/SE2)
 MP/M

1980s
 1980
 86-DOS
 CTOS
 NewDos/80
 OS-9
 SOS
 MVS/System Product (MVS/SP) V1
 Virtual Machine/System Product (VM/SP)
 Xenix
 AOS/VS (Data General)
 1981
 Acorn MOS
 Xinu first release
 Business Operating System
 Aegis SR1 (First Apollo/DOMAIN systems shipped on March 27)
 PC DOS
 Pilot (Xerox Star operating system)
 MS-DOS
 UTS
 iMAX – OS for Intel's iAPX 432 capability machine
 CP/M-86
 1982
 Commodore DOS
 LDOS (By Logical Systems, Inc. – for the Radio Shack TRS-80 Models I, II & III)
 QNX
 Sun UNIX (later SunOS) 0.7
 Ultrix
 Stratus VOS
 Unix System III
 pSOS
 1983
 Lisa Office System 7/7
 Coherent
 GNU (project start)
 Novell NetWare (S-Net)
 ProDOS
 SunOS 1.0
 STOP – TCSEC A1-class, secure OS for SCOMP hardware
 LOCUS – UNIX compatible, high reliability, distributed OS
 DNIX
 MVS/System Product V2 (MVS/Extended Architecture, MVS/XA)
 1984
 AMSDOS
 Mac OS (System 1.0)
 MSX-DOS
 PC/IX
 Sinclair QDOS
 QNX
 UNICOS
 Venix 2.0
 Virtual Machine/Extended Architecture Migration Assistance (VM/XA MA)
 1985
 Windows 1.0
 AmigaOS
 Atari TOS
 DG/UX
 DOS Plus
 MIPS RISC/os
 Oberon – written in Oberon
 SunOS 2.0
 Version 8 Unix
 Windows 1.01 
 Xenix 2.0
 Virtual Machine/Extended Architecture System Facility (VM/XA SF)
 Graphics Environment Manager
 1986
 AIX 1.0
 GS-OS
 Genera 7.0
 HP-UX
 SunOS 3.0
 GEOS
 Version 9 Unix
 GEMSOS – TCSEC A1-class, secure kernel for BLACKER VPN & GTNP
 Cronus distributed OS
 1987
 Topaz – semi-distributed OS for DEC Firefly workstation written in Modula-2+ and garbage collected
 Arthur (much improved version came in 1989 under the name RISC OS)
 IRIX (3.0 is first SGI version)
 MINIX 1.0
 BS2000 V9.0
 OS/2 (1.0)
 PC-MOS/386
 Windows 2.0 
 1988
 A/UX (Apple Computer)
 AOS/VS II (Data General)
 RISC iX
 KeyKOS – capability-based microkernel for IBM mainframes with automated persistence of app data
 LynxOS
 CP/M rebranded as DR-DOS
 Mac OS (System 6)
 MVS/System Product V3 (MVS/Enterprise Systems Architecture, MVS/ESA)
 OS/2 (1.1)
 OS/400
 SpartaDOS X
 SunOS 4.0
 TOPS-10 7.04 (Last stable release, July 1988)
 HeliOS 1.0
 VAX VMM – TCSEC A1-class, VMM for VAX computers (limited use before cancellation)
 Flex machine – tagged, capability machine with OS and other software written in ALGOL 68RS
 Virtual Machine/Extended Architecture System Product (VM/XA SP)
 1989
 EPOC
 NeXTSTEP (1.0)
 OS/2 (1.2)
 RISC OS (First release was to be called Arthur 2, but was renamed to RISC OS 2, and was first sold as RISC OS 2.00 in April 1989)
 SCO UNIX (Release 3)
 TSX-32
 Version 10 Unix
 Xenix 2.3.4 (Last stable release)
 Army Secure Operating System (ASOS) – TCSEC A1-class secure, real-time OS for Ada applications

1990s
 1990
 AmigaOS 2.0
 BeOS (v1)
 DOS/V
 Genera 8.0
 OS/2 1.3
 OSF/1
 AIX 3.0
 MVS/ESA SP Version 4 
 Novell NetWare 3
 Windows 3.0 
 LOCK – TCSEC A1-class secure system with kernel & hardware support for type enforcement
 Virtual Machine/Enterprise Systems Architecture (VM/XA ESA)
 PC/GEOS
 1991
 Linux 0.01-0.1
 Mac OS (System 7)
 MINIX 1.5
 PenPoint OS
 RISC OS 3
 Trusted Xenix – rewritten & security enhanced Xenix evaluated at TCSEC B2-class
 Amoeba – microkernel-based, POSIX-compliant, distributed OS
 1992
 386BSD 0.1
 BSD/386, by BSDi and later known as BSD/OS.
 AmigaOS 3.0
 Amiga Unix 2.01 (Latest stable release)
 RSTS/E 10.1 (Last stable release, September 1992)
 SLS
 Solaris 2.0 (Successor to SunOS 4.x; based on SVR4 instead of BSD)
 OpenVMS V1.0 (First OpenVMS AXP (Alpha) specific version, November 1992)
 OS/2 2.0 (First i386 32-bit based version)
 Plan 9 First Edition (First public release was made available to universities)
 Windows 3.1 
 LGX
 1993
 FreeBSD
 NetBSD
 Newton OS
 Windows NT 3.1 (First Windows NT kernel public release)
 Open Genera 1.0
 IBM 4690 Operating System
 Novell NetWare 4
 OS/2 2.1
 Slackware 1.0
 Spring
 1994
 AIX 4.0, 4.1
 IBM MVS/ESA SP Version 5 
 OS/2 3.0
 RISC OS 3.5
 NetBSD 1.0 (First multi-platform release, October 1994)
 SPIN – extensible OS written in Modula-3
 Red Hat
 1995
 Digital UNIX (aka Tru64 UNIX)
 OpenBSD
 OS/390
 Plan 9 Second Edition (Commercial second release version was made available to the general public.)
 Ultrix 4.5 (Last major release)
 Windows 95
 1996
 Mac OS 7.6 (First officially-named Mac OS)
 Windows NT 4.0
 Windows CE 1.0
 RISC OS 3.6
 AIX 4.2
 OS/2 4.0
 Palm OS
 Debian 1.1
 JN – microkernel OS for embedded, Java apps
 1997
 Inferno
 Mac OS 8
 Windows CE 2.0
 SkyOS
 MINIX 2.0
 RISC OS 3.7
 AIX 4.3
 DR-WebSpyder 1.0
 Nemesis
 1998
 Solaris 7 (first 64-bit Solaris release – names from this point drop "2.", otherwise would've been Solaris 2.7)
 Windows 98
 RT-11 5.7 (Last stable release, October 1998)
 Novell NetWare 5
 Junos
 DR-WebSpyder 2.0
 1999
 AROS (Boot for the first time in Stand Alone version)
 RISC OS 4
 Mac OS 9
 OS/2 4.5
 Windows 98 (2nd edition)
 Inferno Second Edition (Last distribution (Release 2.3, ) from Lucent's Inferno Business Unit)

2000s

2010s

2020s

See also
 Comparison of operating systems
 List of operating systems
 Comparison of real-time operating systems
 Timeline of DOS operating systems
 Timeline of Linux distributions (Diagram 1992–2010)

References

External links
 UNIX History – a timeline of UNIX 1969 and its descendants at present
 Concise Microsoft O.S. Timeline – a color-coded concise timeline for various Microsoft operating systems (1981–present)
Full Form of Computer - Full Form and Working of Computers.
 Bitsavers – an effort to capture, salvage, and archive historical computer software and manuals from minicomputers and mainframes of the 1950s, 1960s, 1970s, and 1980s
 A brief history of operating systems
 Microsoft operating system time-line

Timeline of operating systems
Operating systems
Operating systems
Real-time operating systems
Embedded operating systems