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 The Electronic Delay Storage Automatic Calculator (EDSAC) was an early British computer. Inspired by John von Neumann's seminal ''First Draft of a Report on the EDVAC'', the machine was constructed by Maurice Wilkes and his team at the Universi ...

computing platform, supported by British firm

J. Lyons and Co. J. Lyons & Co. was a British restaurant Chain store, chain, food manufacturing, and hotel conglomerate founded in 1884 by Joseph Lyons (caterer), Joseph Lyons and his brothers in law, Isidore Gluckstein, Isidore and Montague Gluckstein. Lyons’ ...

* 1955 ** MIT's Tape Director operating system made for UNIVAC 1103 * 1955 ** General Motors Operating System made for

IBM 701 The IBM 701 Electronic Data Processing Machine, known as the Defense Calculator while in development, was IBM’s first commercial scientific computer and its first series production mainframe computer, which was announced to the public on May ...

* 1956 ** GM-NAA I/O for

IBM 704 The IBM 704 is a large digital mainframe computer introduced by IBM in 1954. It was the first mass-produced computer with hardware for floating-point arithmetic. The IBM 704 ''Manual of operation'' states: The type 704 Electronic Data-Pro ...

, based on General Motors Operating System * 1957 ** Atlas Supervisor ( Manchester University) (''Atlas computer project start'') ** BESYS ( Bell Labs), for

, later IBM 7090 and

IBM 7094 The IBM 7090 is a second-generation transistorized version of the earlier IBM 709 vacuum tube mainframe computer that was designed for "large-scale scientific and technological applications". The 7090 is the fourth member of the IBM 700/7000 ser ...

* 1958 **

University of Michigan Executive System The University of Michigan Executive System, or UMES, a batch operating system developed at the University of Michigan in 1958, was widely used at many universities. Based on the General Motors Executive System for the IBM 701, UMES was revised ...

(UMES), for IBM 704,

709 __NOTOC__ Year 709 ( DCCIX) was a common year starting on Tuesday (link will display the full calendar) of the Julian calendar. The denomination 709 for this year has been used since the early medieval period, when the Anno Domini calendar era ...

, 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

) ** 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 The AN/FSQ-32 SAGE Solid State Computer (AN/FSQ-7A before December 1958, colloq. "Q-32") was a planned military computer central for deployment to Super Combat Centers in nuclear bunkers and to some above-ground military installations. In 1958, ...

, another early time-sharing system begun ** CTSS becomes operational ( MIT's Compatible Time-Sharing System for the

) ** 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 N.º UIC: 9094 110 1449-3 (Takargo Rail) The English Electric Company Limited (EE) was a British industrial manufacturer formed after the Armistice of 11 November 1918, armistice of World War I by amalgamating five businesses which, during th ...

) – 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 Scope or scopes may refer to: People with the surname * Jamie Scope (born 1986), English footballer * John T. Scopes (1900–1970), central figure in the Scopes Trial regarding the teaching of evolution Arts, media, and entertainment * CinemaS ...

(CDC 3000 series) ** PDP-6 Monitor ( DEC) descendant renamed TOPS-10 in 1970 ** EXEC 8 ( UNIVAC) * 1965 ** THE multiprogramming system (

Technische Hogeschool Eindhoven The Eindhoven University of Technology ( nl, Technische Universiteit Eindhoven), abbr. TU/e, is a public technical university in the Netherlands, located in the city of Eindhoven. In 2020–21, around 14,000 students were enrolled in its BSc a ...

) 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 Disk Operating System/360, also DOS/360, or simply DOS, is the discontinued first member of a sequence of operating systems for IBM System/360, System/370 and later mainframes. It was announced by IBM on the last day of 1964, and it was first d ...

(IBM's Disk Operating System) **

MS/8 MS/8 or The RL Monitor System is a discontinued computer operating system developed for the Digital Equipment Corporation PDP-8 in 1966 by Richard F. Lary. History RL Monitor System, as it was initially called, was developed on a 4K (12-bit) PD ...

(

Richard F. Lary Richard F. "Richie" Lary (born 1948, Brooklyn, New York) is the ''RL'' of the PDP-8 '' RL Monitor System'', which subsequently became ''MS/8''. Years later, while working for Digital Equipment Corporation, he was also involved with other ''DEC' ...

's DEC PDP-8 system) ** GEORGE 1 & 2 for

ICT ICT may refer to: Sciences and technology * Information and communications technology * Image Constraint Token, in video processing * Immunochromatographic test, a rapid immunoassay used to detect diseases such as anthrax * In-circuit test, in ...

1900 series ** Remote Users of Shared Hardware (RUSH), a time-sharing system developed by

Allen-Babcock Allen-Babcock Computing was founded in Los Angeles in 1964 by James D. Babcock and Michael Jane Allen Babcock to take advantage of the fast-growing market for computer time-sharing services. In 1966 the company developed "RUSH" (Remote Users of Sha ...

for the 360/50 ** 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) ** Conversational Programming System (CPS), an IBM time-sharing system under OS/360 ** 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/360-67) ** 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 A sail is a tensile structure—which is made from fabric or other membrane materials—that uses wind power to propel sailing craft, including sailing ships, sailboats, windsurfers, ice boats, and even sail-powered land vehicles. Sails may ...

, Stanford Artificial Intelligence Laboratory, time-sharing system for DEC PDP-6 and PDP-10, later TOPS-10) * 1968 ** Airline Control Program (ACP) (IBM) ** CALL/360, an IBM time-sharing system for System/360 ** THE multiprogramming system ( Eindhoven University of Technology) publication **

TSS/8 TSS/8 is a discontinued time-sharing operating system co-written by Don Witcraft and John Everett at Digital Equipment Corporation in 1967. DEC also referred to it as Timeshared-8 and EduSystem 50. The operating system runs on the 12-bit PDP-8 co ...

(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 GEORGE was the name given to a series of operating systems released by International Computers and Tabulators (ICT) in the 1960s, for the ICT 1900 series of computers. These included GEORGE 1, GEORGE 2, GEORGE 3, and GEORGE 4. Initially the 19 ...

For

ICL ICL may refer to: Companies and organizations * Idaho Conservation League * Imperial College London, a UK university * Indian Confederation of Labour * Indian Cricket League * Inorganic Chemistry Laboratory of the University of Oxford * Israel Ch ...

1900 series

1970s

* 1970 ** DOS-11 (PDP-11) * 1971 **

RSTS-11 RSTS () is a multi-user time-sharing operating system developed by Digital Equipment Corporation (DEC, now part of Hewlett-Packard) for the PDP-11 series of 16-bit minicomputers. The first version of RSTS (RSTS-11, #Versions, Version 1) was implem ...

2A-19 (''First released version; PDP-11'') ** OS/8 * 1972 ** Data General RDOS ** Edos ** MUSIC/SP ** Operating System/Virtual Storage 1 (OS/VS1) ** Operating System/Virtual Storage 2 R1 (OS/VS2 SVS) **

PRIMOS PRIMOS is a discontinued operating system developed during the 1970s by Prime Computer for its minicomputer systems. It rapidly gained popularity and by the mid-1980s was a serious contender as a mainline minicomputer operating system. With ...

(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 The PL/P programming language (an acronym of ''Programming Language for Prime (computers)'') is a mid-level programming language developed by Prime Computer to serve as their second primary system programming language after Fortran IV. PL/P was a ...

) ** Virtual Machine/Basic System Extensions Program Product (BSEPP or VM/SE) ** Virtual Machine/System Extensions Program Product (SEPP or VM/BSE) ** Virtual Machine Facility/370 (VM/370), sometimes known as VM/CMS * 1973 ** Эльбрус-1 ( Elbrus-1) – Soviet computer – created using high-level language uЭль-76 ( AL-76/ALGOL 68) ** Alto OS ** RSX-11D ** RT-11 ** VME – implementation language S3 ( ALGOL 68) * 1974 **

CP/M CP/M, originally standing for Control Program/Monitor and later Control Program for Microcomputers, is a mass-market operating system created in 1974 for Intel 8080/ 85-based microcomputers by Gary Kildall of Digital Research, Inc. Initial ...

** DOS-11 V09-20C (''Last stable release, June 1974'') **

MONECS MONECS ( Monash University Educational Computing System) was a computer operating system with BASIC, COBOL, FORTRAN, Pascal interpreters, plus machine language facility. Specifically designed for computer science education in Australian secondar ...

Multi-Programming Executive MPE (Multi-Programming Executive) is a discontinued business-oriented mainframe computer real-time operating system made by Hewlett-Packard. While initially a mini-mainframe, the final high-end systems supported 12 CPUs and over 2000 simultane ...

(MPE) – Hewlett-Packard ** Hydra – capability-based, multiprocessing OS kernel ** Operating System/Virtual Storage 2 R2 (MVS) ** Sintran III * 1975 ** BS2000 V2.0 (''First released version'') ** Version 6 Unix * 1976 **

Cambridge CAP computer The Cambridge CAP computer was the first successful experimental computer that demonstrated the use of security capabilities, both in hardware and software.Levy, p.96 It was developed at the University of Cambridge Computer Laboratory in the 19 ...

– all operating system procedures written in ALGOL 68C, with some closely associated protected procedures in

BCPL BCPL ("Basic Combined Programming Language") is a procedural, imperative, and structured programming language. Originally intended for writing compilers for other languages, BCPL is no longer in common use. However, its influence is still ...

** Cray Operating System **

FLEX Flex or FLEX may refer to: Computing * Flex (language), developed by Alan Kay * FLEX (operating system), a single-tasking operating system for the Motorola 6800 * FlexOS, an operating system developed by Digital Research * FLEX (protocol), a comm ...

** TOPS-20 ** Tandem Nonstop OS v1 * 1977 ** 1BSD ** KERNAL **

OASIS operating system THEOS, which translates from Greek as "God", is an operating system which started out as OASIS, a microcomputer operating system for small computers that use the Z80 processor. When the operating system was launched for the IBM Personal Comp ...

** OS68 **

OS4000 OS4000 is a proprietary operating system introduced by GEC Computers Limited in 1977 as the successor to GEC DOS, for its range of GEC 4000 series 16-bit, and later 32-bit, minicomputers. OS4000 was developed through to late 1990s, and has bee ...

** System Support Program (IBM System/34 and System/36) ** TRSDOS ** Virtual Memory System (VMS) V1.0 (''Initial commercial release, October 25'') * 1978 **

2BSD The History of the Berkeley Software Distribution begins in the 1970s. 1BSD (PDP-11) The earliest distributions of Unix from Bell Labs in the 1970s included the source code to the operating system, allowing researchers at universities to modify an ...

Apple DOS Apple DOS is the family of disk operating systems for the Apple II series of microcomputers from late 1978 through early 1983. It was superseded by ProDOS in 1983. Apple DOS has three major releases: DOS 3.1, DOS 3.2, and DOS 3.3; each one of t ...

** Control Program Facility (IBM System/38) ** HDOS ** KSOS – secure OS design from Ford Aerospace ** KVM/370 – security retro-fit of IBM VM/370 ** Lisp machine (CADR) ** MVS/System Extensions (MVS/SE) ** PTDOS ** TRIPOS ** UCSD p-System (''First released version'') * 1979 ** Atari DOS **

3BSD The History of the Berkeley Software Distribution begins in the 1970s. 1BSD (PDP-11) The earliest distributions of Unix from Bell Labs in the 1970s included the source code to the operating system, allowing researchers at universities to modify an ...

Idris Idris may refer to: People * Idris (name), a list of people and fictional characters with the given name or surname * Idris (prophet), Islamic prophet in the Qur'an, traditionally identified with Enoch, an ancestor of Noah in the Bible * Idris G ...

** MP/M ** MVS/System Extensions R2 (MVS/SE2) **

NLTSS The Network Livermore Timesharing System (NLTSS, also sometimes the New Livermore Time Sharing System) is an operating system that was actively developed at Lawrence Livermore Laboratory (now Lawrence Livermore National Laboratory) from 1979 until ...

POS POS, Pos or PoS may refer to: Linguistics * Part of speech, the role that a word or phrase plays in a sentence * Poverty of the stimulus, a linguistic term used in language acquisition and development * Sayula Popoluca (ISO 639-3), an indigenous l ...

Sinclair BASIC Sinclair BASIC is a dialect of the programming language BASIC used in the 8-bit home computers from Sinclair Research and Timex Sinclair. The Sinclair BASIC interpreter was made by Nine Tiles Networks Ltd. History Sinclair BASIC was orig ...

** UCLA Secure UNIX – an early secure UNIX OS based on security kernel ** UNIX/32V ** Version 7 Unix

1980s

* 1980 **

86-DOS 86-DOS (known internally as QDOS, for Quick and Dirty Operating System) is a discontinued operating system developed and marketed by Seattle Computer Products (SCP) for its Intel 8086-based computer kit. 86-DOS shared a few of its commands wit ...

** AOS/VS (Data General) **

CTOS The Convergent Technologies Operating System, also known variously as CTOS, BTOS and STARSYS, is a discontinued modular, message-passing, multiprocess-based operating system. Overview CTOS had many innovative features for its time. System access ...

** MVS/System Product (MVS/SP) V1 **

NewDos/80 NewDos/80 is a third-party operating system for the Radio Shack TRS-80 line of microcomputers released in 1980. NewDos/80 was developed by Apparat, Inc. of Denver, Colorado. NewDos/80 version 2.0 was released in August 1981. It ran on the TRS-80 ...

** OS-9 **

SOS is a Morse code distress signal (), used internationally, that was originally established for maritime use. In formal notation is written with an overscore line, to indicate that the Morse code equivalents for the individual letters of "SOS" ...

** Virtual Machine/System Product (VM/SP) ** Xenix * 1981 ** Acorn MOS ** Aegis SR1 (''First Apollo/DOMAIN systems shipped on March 27'') ** Business Operating System **

CP/M-86 CP/M-86 was a version of the CP/M operating system that Digital Research (DR) made for the Intel 8086 and Intel 8088. The system commands are the same as in CP/M-80. Executable files used the relocatable .CMD file format. Digital Research als ...

iMAX IMAX is a proprietary system of high-resolution cameras, film formats, film projectors, and theaters known for having very large screens with a tall aspect ratio (approximately either 1.43:1 or 1.90:1) and steep stadium seating. Graeme F ...

– OS for Intel's iAPX 432 capability machine ** MS-DOS ** PC DOS ** Pilot ('' Xerox Star operating system'') **

UNOS The United Network for Organ Sharing (UNOS) is a non-profit, scientific and educational organization that administers the only Organ Procurement and Transplantation Network (OPTN) in the United States, established () by the U.S. Congress in 1984 b ...

** UTS ** Xinu first release * 1982 ** Commodore DOS ** LDOS (By Logical Systems, Inc. – for the Radio Shack TRS-80 Models I, II & III) **

pSOS PSOS, ''PSOs'' or pSOS may refer to: * pSOS (real-time operating system) * Provably Secure Operating System * Project Support Open Source * Protective services officers * The Police Service of Scotland Police Scotland ( gd, Poileas Alba), off ...

** QNX ** Stratus VOS ** Sun UNIX (later

SunOS SunOS is a Unix-branded operating system developed by Sun Microsystems for their workstation and server computer systems. The ''SunOS'' name is usually only used to refer to versions 1.0 to 4.1.4, which were based on BSD, while versions 5.0 and l ...

) 0.7 **

Ultrix Ultrix (officially all-caps ULTRIX) is the brand name of Digital Equipment Corporation's (DEC) discontinued native Unix operating systems for the PDP-11, VAX, MicroVAX and DECstations. History The initial development of Unix occurred on DEC equip ...

** Unix System III * 1983 ** Coherent ** DNIX ** EOS ** GNU (''project start'') ** Lisa Office System 7/7 ** LOCUS – UNIX compatible, high reliability, distributed OS ** MVS/System Product V2 (MVS/Extended Architecture, MVS/XA) ** Novell NetWare (

S-Net S-Net is a worldwide inter-satellite communications network consisting of four satellites and being operated by the Technical University of Berlin. Description The project has the goal to investigate and demonstrate inter-satellite communication t ...

) ** ProDOS ** STOP – TCSEC A1-class, secure OS for SCOMP hardware **

1.0 * 1984 ** AMSDOS ** Mac OS (''System 1.0'') ** MSX-DOS **

PC/IX Interactive Systems Corporation (styled INTERACTIVE Systems Corporation, abbreviated ISC) was a US-based software company and the first vendor of the Unix operating system outside AT&T, operating from Santa Monica, California. It was founded in 19 ...

** Sinclair QDOS ** QNX **

UNICOS UNICOS is a range of Unix and after it Linux operating system (OS) variants developed by Cray for its supercomputers. UNICOS is the successor of the Cray Operating System (COS). It provides network clustering and source code compatibility la ...

** Venix 2.0 ** Virtual Machine/Extended Architecture Migration Assistance (VM/XA MA) * 1985 ** AmigaOS **

Atari TOS TOS (The Operating System) is the operating system of the Atari ST range of computers. This range includes the 520ST and 1040ST, their STF/M/FM and STE variants and the Mega ST/STE. Later, 32-bit machines ( TT, Falcon030) were developed using a ...

** DG/UX ** DOS Plus ** Graphics Environment Manager ** MIPS RISC/os ** Oberon – written in Oberon **

2.0 ** Version 8 Unix ** Virtual Machine/Extended Architecture System Facility (VM/XA SF) ** Windows 1.0 ** Windows 1.01 ** Xenix 2.0 * 1986 ** AIX 1.0 ** Cronus distributed OS ** GEMSOS – TCSEC A1-class, secure kernel for BLACKER VPN & GTNP **

GEOS #REDIRECT GEOS {{redirect category shell, {{R from other capitalisation{{R from ambiguous page ...

** GS-OS **

Genera Genus ( plural genera ) is a taxonomic rank used in the biological classification of living and fossil organisms as well as viruses. In the hierarchy of biological classification, genus comes above species and below family. In binomial nomenclat ...

7.0 **

HP-UX HP-UX (from "Hewlett Packard Unix") is Hewlett Packard Enterprise's proprietary implementation of the Unix operating system, based on Unix System V (initially System III) and first released in 1984. Current versions support HPE Integrity Ser ...

3.0 **

Version 9 Unix The term "Research Unix" refers to early versions of the Unix operating system for PDP-7, DEC PDP-7, PDP-11, VAX and Interdata 7/32 and 8/32 computers, developed in the Bell Labs Computing Sciences Research Center (CSRC). History The term ''Re ...

* 1987 ** Arthur (much improved version came in 1989 under the name RISC OS) ** BS2000 V9.0 **

IRIX IRIX ( ) is a discontinued operating system developed by Silicon Graphics (SGI) to run on the company's proprietary MIPS workstations and servers. It is based on UNIX System V with BSD extensions. In IRIX, SGI originated the XFS file system and ...

(''3.0 is first SGI version'') ** MDOS ** MINIX 1.0 ** OS/2 (1.0) ** PC-MOS/386 ** Topaz – semi-distributed OS for DEC Firefly workstation written in Modula-2+ and garbage collected **

Windows 2.0 Windows 2.0 is a major release of Microsoft Windows, a family of graphical operating systems for personal computers developed by Microsoft. It was released to manufacturing on December 9, 1987, as a successor to Windows 1.0. The product includ ...

* 1988 ** A/UX (Apple Computer) **

AOS/VS II AOS/VS II is a discontinued operating system for the Data General 32-bit MV/Eclipse computers. Overview The AOS/VS II operating system was released in 1988 and was originally to be simply rev 8.00 of the AOS/VS operating system. However, it int ...

(Data General) **

rebranded as

DR-DOS DR-DOS (written as DR DOS, without a hyphen, in versions up to and including 6.0) is a disk operating system for IBM PC compatibles. Upon its introduction in 1988, it was the first DOS attempting to be compatible with IBM PC DOS and MS-D ...

** Flex machine – tagged, capability machine with OS and other software written in ALGOL 68RS **

HeliOS In ancient Greek religion and Greek mythology, mythology, Helios (; grc, , , Sun; Homeric Greek: ) is the deity, god and personification of the Sun (Solar deity). His name is also Latinized as Helius, and he is often given the epithets Hyper ...

1.0 ** KeyKOS – capability-based microkernel for IBM mainframes with automated persistence of app data ** LynxOS ** Mac OS (''

System 6 System 6 (or System Software 6) is a graphical user interface-based operating system for Macintosh computers, made by Apple Computer It was released in 1988, and is part of the classic Mac OS series. It is a monolithic operating system, with coop ...

'') ** MVS/System Product V3 (MVS/Enterprise Systems Architecture, MVS/ESA) ** OS/2 (1.1) ** OS/400 ** RISC iX ** SpartaDOS X **

4.0 ** TOPS-10 7.04 (''Last stable release, July 1988'') ** Virtual Machine/Extended Architecture System Product (VM/XA SP) ** VAX VMM – TCSEC A1-class, VMM for VAX computers (limited use before cancellation) * 1989 ** Army Secure Operating System (ASOS) – TCSEC A1-class secure, real-time OS for Ada applications ** TSX-32 **

Version 10 Unix The term "Research Unix" refers to early versions of the Unix operating system for DEC PDP-7, PDP-11, VAX and Interdata 7/32 and 8/32 computers, developed in the Bell Labs Computing Sciences Research Center (CSRC). History The term ''Researc ...

** Xenix 2.3.4 (''Last stable release'')

1990s

* 1990 ** AIX 3.0 ** AmigaOS 2.0 **

BeOS BeOS is an operating system for personal computers first developed by Be Inc. in 1990. It was first written to run on BeBox hardware. BeOS was positioned as a multimedia platform that could be used by a substantial population of desktop users a ...

(v1) ** DOS/V **

8.0 ** LOCK – TCSEC A1-class secure system with kernel & hardware support for type enforcement ** MVS/ESA SP Version 4 ** Novell NetWare 3 ** OS/2 1.3 **

OSF/1 OSF/1 is a variant of the Unix operating system developed by the Open Software Foundation during the late 1980s and early 1990s. OSF/1 is one of the first operating systems to have used the Mach kernel developed at Carnegie Mellon University, and ...

** PC/GEOS ** Windows 3.0 ** Virtual Machine/Enterprise Systems Architecture (VM/XA ESA) * 1991 ** Amoeba – microkernel-based, POSIX-compliant, distributed OS ** 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 * 1992 **

386BSD 386BSD (also known as "Jolix") is a discontinued Unix operating system based on the Berkeley Software Distribution (BSD). It was released in 1992 and ran on PC-compatible computer systems based on the 32-bit Intel 80386 microprocessor. 386BSD inn ...

0.1 **

Amiga Unix Amiga Unix (informally known as Amix) is a discontinued full port of AT&T Unix System V Release 4 operating system developed by Commodore-Amiga, Inc. in 1990 for the Amiga computer family as an alternative to AmigaOS, which shipped by default. O ...

2.01 (''Latest stable release'') ** AmigaOS 3.0 ** BSD/386, by

BSDi Berkeley Software Design, Inc. (BSDI or, later, BSDi), was a corporation which developed, sold licenses for, and supported BSD/OS (originally known as BSD/386), a commercial and partially proprietary variant of the BSD Unix operating system for ...

and later known as BSD/OS. ** LGX **

OpenVMS OpenVMS, often referred to as just VMS, is a multi-user, multiprocessing and virtual memory-based operating system. It is designed to support time-sharing, batch processing, transaction processing and workstation applications. Customers using Ope ...

V1.0 (''First OpenVMS AXP (Alpha) specific version, November 1992'') ** OS/2 2.0 (First i386 32-bit based version) **

Plan 9 Plan 9 or Plan Nine may refer to: Music * Plan 9 (band), a psychedelic rock band from Rhode Island * ''Plan 9'', an album by Big Guitars From Memphis with Rick Lindy * "Plan 9", a song on the 1993 album ''Gorgeous'' by electronica band 808 Stat ...

First Edition (''First public release was made available to universities'') ** RSTS/E 10.1 (''Last stable release, September 1992'') **

SLS SLS may refer to the Space Launch System, a launch vehicle developed by NASA. It may also refer to: Education * Stanford Law School, California, U.S. * Sydney Law School, Australia * Symbiosis Law School, India * Same language subtitling, of TV ...

Solaris Solaris may refer to: Arts and entertainment Literature, television and film * ''Solaris'' (novel), a 1961 science fiction novel by Stanisław Lem ** ''Solaris'' (1968 film), directed by Boris Nirenburg ** ''Solaris'' (1972 film), directed by ...

2.0 (''Successor to SunOS 4.x; based on SVR4 instead of BSD'') ** Windows 3.1 * 1993 ** IBM 4690 Operating System **

FreeBSD FreeBSD is a free and open-source Unix-like operating system descended from the Berkeley Software Distribution (BSD), which was based on Research Unix. The first version of FreeBSD was released in 1993. In 2005, FreeBSD was the most popular ...

NetBSD NetBSD is a free and open-source Unix operating system based on the Berkeley Software Distribution (BSD). It was the first open-source BSD descendant officially released after 386BSD was forked. It continues to be actively developed and is a ...

** Novell NetWare 4 ** Newton OS ** Open Genera 1.0 ** OS/2 2.1 ** Slackware 1.0 ** Spring ** Windows NT 3.1 (''First Windows NT kernel public release'') * 1994 ** AIX 4.0, 4.1 ** IBM MVS/ESA SP Version 5 **

1.0 (''First multi-platform release, October 1994'') ** OS/2 3.0 **

Red Hat Red Hat, Inc. is an American software company that provides open source software products to enterprises. Founded in 1993, Red Hat has its corporate headquarters in Raleigh, North Carolina, with other offices worldwide. Red Hat has become ass ...

** RISC OS 3.5 **

SPIN Spin or spinning most often refers to: * Spinning (textiles), the creation of yarn or thread by twisting fibers together, traditionally by hand spinning * Spin, the rotation of an object around a central axis * Spin (propaganda), an intentionally b ...

– extensible OS written in Modula-3 * 1995 ** Digital UNIX (''aka'' Tru64 UNIX) **

OpenBSD OpenBSD is a security-focused, free and open-source, Unix-like operating system based on the Berkeley Software Distribution (BSD). Theo de Raadt created OpenBSD in 1995 by forking NetBSD 1.0. According to the website, the OpenBSD project em ...

** OS/390 **

Second Edition (''Commercial second release version was made available to the general public.'') **

4.5 (''Last major release'') ** Windows 95 * 1996 ** AIX 4.2 **

Debian Debian (), also known as Debian GNU/Linux, is a Linux distribution composed of free and open-source software, developed by the community-supported Debian Project, which was established by Ian Murdock on August 16, 1993. The first version of D ...

1.1 ** JN – microkernel OS for embedded, Java apps ** Mac OS 7.6 (''First officially-named Mac OS'') ** OS/2 4.0 ** Palm OS ** RISC OS 3.6 ** Windows NT 4.0 **

Windows CE 1.0 Windows Embedded Compact, formerly Windows Embedded CE, Windows Powered and Windows CE, is an operating system subfamily developed by Microsoft as part of its Windows Embedded family of products. Unlike Windows Embedded Standard, which is base ...

* 1997 ** AIX 4.3 **

DR-WebSpyder DR-WebSpyder is a DOS web browser, mail client and operating system runtime environment that was developed by Caldera UK in 1997. It was based on the DR-DOS operating system and networking components from Novell as well as the Arachne web brow ...

1.0 ** Inferno ** Mac OS 8 ** MINIX 2.0 **

Nemesis In ancient Greek religion, Nemesis, also called Rhamnousia or Rhamnusia ( grc, Ῥαμνουσία, Rhamnousía, the goddess of Rhamnous), was the goddess who personifies retribution, a central concept in the Greek world view. Etymology The n ...

** RISC OS 3.7 ** SkyOS **

Windows CE 2.0 Windows Embedded Compact, formerly Windows Embedded CE, Windows Powered and Windows CE, is an operating system subfamily developed by Microsoft as part of its Windows Embedded family of products. Unlike Windows Embedded Standard, which is base ...

* 1998 **

2.0 **

Junos Junos OS (also known as Juniper Junos, Junos and JUNOS) is a FreeBSD-based network operating system used in Juniper Networks routing, switching and security devices. Versioning Junos OS was first made available on 7 July 1998, with new feature ...

** Novell NetWare 5 ** RT-11 5.7 (''Last stable release, October 1998'') **

7 (''first 64-bit Solaris release – names from this point drop "2.", otherwise would've been Solaris 2.7'') ** Windows 98 * 1999 ** AROS (''Boot for the first time in Stand Alone version'') ** Inferno Second Edition (''Last distribution (Release 2.3, ) from Lucent's Inferno Business Unit'') **

Mac OS 9 Mac OS 9 is the ninth major release of Apple Inc., Apple's classic Mac OS operating system which was succeeded by macOS, Mac OS X (renamed to OS X in 2011 and macOS in 2016) in 2001. Introduced on October 23, 1999, it was promoted by Apple as "T ...

** OS/2 4.5 ** RISC OS 4 ** Windows 98 (2nd edition)

2000s

2010s

2020s

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 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
{{Timelines of computing *Timeline of operating systems

Operating systems An operating system (OS) is system software that manages computer hardware, software resources, and provides common services for computer programs. Time-sharing operating systems schedule tasks for efficient use of the system and may also inc ...

Real-time operating systems Embedded operating systems