This article presents a

timeline A timeline is a list of events displayed in chronological order. It is typically a graphic design showing a long bar labelled with dates paralleling it, and usually contemporaneous events. Timelines can use any suitable scale representing t ...

of events in the history of computer

operating system An operating system (OS) is system software that manages computer hardware and software resources, and provides common daemon (computing), services for computer programs. Time-sharing operating systems scheduler (computing), schedule tasks for ...

s 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 Universit ...

computing platform, supported by British firm

J. Lyons and Co. J, or j, is the tenth letter of the English alphabet. J may also refer to: * Palatal approximant in the International Phonetic Alphabet * J, Cyrillic letter Je Astronomy * J, a provisional designation prefix for some objects discovered be ...

* 1953 ** DYSEAC - an early machine capable of distributing computing * 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 2 ...

MIT The Massachusetts Institute of Technology (MIT) is a private research university in Cambridge, Massachusetts, United States. Established in 1861, MIT has played a significant role in the development of many areas of modern technology and sc ...

's Tape Director operating system made for UNIVAC 1103 * 1956 ** GM-NAA I/O for

IBM 704 The IBM 704 is the model name of a large digital computer, digital mainframe computer introduced by IBM in 1954. Designed by John Backus and Gene Amdahl, it was the first mass-produced computer with hardware for floating-point arithmetic. The I ...

, based on General Motors Operating System * 1957 **

Atlas Supervisor The Atlas Supervisor was the program which managed the allocation of processing resources of Manchester University's Atlas Computer so that the machine was able to act on many tasks and user programs concurrently. Its various functions includ ...

(

Manchester University The University of Manchester is a public university, public research university in Manchester, England. The main campus is south of Manchester city centre, Manchester City Centre on Wilmslow Road, Oxford Road. The University of Manchester is c ...

) (''Atlas computer project start'') ** BESYS (

Bell Labs Nokia Bell Labs, commonly referred to as ''Bell Labs'', is an American industrial research and development company owned by Finnish technology company Nokia. With headquarters located in Murray Hill, New Jersey, Murray Hill, New Jersey, the compa ...

), for

, later

IBM 7090 The IBM 7090 is a second-generation Transistor computer, 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 o ...

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 se ...

* 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 International Business Machines Corporation (using the trademark IBM), nicknamed Big Blue, is an American Multinational corporation, multinational technology company headquartered in Armonk, New York, and present in over 175 countries. It is ...

for its 7090 and 7094) * 1961 ** CTSS demonstration ( MIT's Compatible Time-Sharing System for the

) ** MCP ( Burroughs Master Control Program) for

B5000 The Burroughs Large Systems Group produced a family of large 48-bit mainframes using stack machine instruction sets with dense syllables.E.g., 12-bit syllables for B5000, 8-bit syllables for B6500 The first machine in the family was the B5000 i ...

* 1962 **

(

) (''Atlas computer commissioned'') **

BBN Time-Sharing System The BBN Time-Sharing System was an early time-sharing system created at Bolt, Beranek and Newman (BBN) for the PDP-1 computer. It began operation in September 1962. History J. C. R. Licklider left MIT to become a vice president at Bolt Beran ...

** GCOS ( GE's General Comprehensive Operating System, originally GECOS, General Electric Comprehensive Operating Supervisor) * 1963 **

ADMIRAL Admiral is one of the highest ranks in many navies. In the Commonwealth nations and the United States, a "full" admiral is equivalent to a "full" general in the army or the air force. Admiral is ranked above vice admiral and below admiral of ...

** AN/FSQ-32, another early time-sharing system begun ** CTSS becomes operational ( MIT's Compatible Time-Sharing System for the

) **

JOSS JOSS (acronym for JOHNNIAC Open Shop System) was one of the first interactive, time-sharing programming languages. It pioneered many features that would become common in languages from the 1960s into the 1980s, including use of line numbers as bo ...

, an interactive time-shared system that did not distinguish between operating system and language ** Titan Supervisor, early time-sharing system begun * 1964 **

Berkeley Timesharing System The Berkeley Timesharing System was a pioneering time-sharing operating system implemented between 1964 and 1967 at the University of California, Berkeley. It was designed as part of Project Genie and marketed by Scientific Data Systems for the ...

(for

Scientific Data Systems Scientific Data Systems (SDS), was an American computer company founded in September 1961 by Max Palevsky, Arthur Rock and Robert Beck, veterans of Packard Bell Corporation and Bendix, along with eleven other computer scientists. SDS was the f ...

SDS 940 The SDS 940 was Scientific Data Systems' (SDS) first machine designed to directly support time-sharing. The 940 was based on the SDS 930's 24-bit CPU, with additional circuitry to provide protected memory and virtual memory. It was announced in ...

) ** Chippewa Operating System (for

CDC 6600 The CDC 6600 was the flagship of the 6000 series of mainframe computer systems manufactured by Control Data Corporation. Generally considered to be the first successful supercomputer, it outperformed the industry's prior recordholder, the I ...

supercomputer) **

Dartmouth Time-Sharing System The Dartmouth Time-Sharing System (DTSS) is a discontinued operating system first developed at Dartmouth College between 1963 and 1964. It was the first successful large-scale time-sharing system to be implemented, and was also the system for wh ...

(

Dartmouth College Dartmouth College ( ) is a Private university, private Ivy League research university in Hanover, New Hampshire, United States. Established in 1769 by Eleazar Wheelock, Dartmouth is one of the nine colonial colleges chartered before the America ...

's DTSS for GE computers) ** EXEC 8 (

UNIVAC UNIVAC (Universal Automatic Computer) was a line of electronic digital stored-program computers starting with the products of the Eckert–Mauchly Computer Corporation. Later the name was applied to a division of the Remington Rand company and ...

) ** KDF9 Timesharing Director (

English Electric The English Electric Company Limited (EE) was a British industrial manufacturer formed after World War I by amalgamating five businesses which, during the war, made munitions, armaments and aeroplanes. It initially specialised in industrial el ...

) – an early, fully hardware secured, fully pre-emptive process switching, multi-programming operating system for KDF9 (originally announced in 1960) **

OS/360 OS/360, officially known as IBM System/360 Operating System, is a discontinued batch processing operating system developed by IBM for their then-new System/360 mainframe computer, announced in 1964; it was influenced by the earlier IBSYS/IBJOB a ...

(IBM's primary OS for its S/360 series) (''announced'') ** PDP-6 Monitor ( DEC) descendant renamed

TOPS-10 TOPS-10 System (Timesharing / Total Operating System-10) is a discontinued operating system from Digital Equipment Corporation (DEC) for the PDP-10 (or DECsystem-10) mainframe computer family. Launched in 1967, TOPS-10 evolved from the earlier "Mo ...

in 1970 ** SCOPE (CDC 3000 series) * 1965 ** BOS/360 (IBM's Basic Operating System) ** DECsys ** TOS/360 (IBM's Tape Operating System) ** Livermore Time Sharing System (LTSS) **

Multics Multics ("MULTiplexed Information and Computing Service") is an influential early time-sharing operating system based on the concept of a single-level memory.Dennis M. Ritchie, "The Evolution of the Unix Time-sharing System", Communications of t ...

(MIT, GE,

for the

GE-645 The GE 645 mainframe computer was a development of the GE 635 for use in the Multics project. This was the first computer that implemented a configurable hardware protected memory system. It was designed to satisfy the requirements of Project MAC ...

) (''announced'') **

Pick operating system The Pick Operating System, also known as the Pick System or simply Pick, is a demand-paged, multi-user, virtual memory, time-sharing computer operating system based around a MultiValue database. Pick is used primarily for business data processin ...

** SIPROS 66 (Simultaneous Processing Operating System) **

THE multiprogramming system The THE multiprogramming system or THE OS was a computer operating system designed by a team led by Edsger W. Dijkstra, described in monographs in 1965-66 (Jun 14, 1965) and published in 1968. Dijkstra never named the system; "THE" is simply ...

( Technische Hogeschool Eindhoven) development ** TSOS (later VMOS) (

RCA RCA Corporation was a major American electronics company, which was founded in 1919 as the Radio Corporation of America. It was initially a patent pool, patent trust owned by General Electric (GE), Westinghouse Electric Corporation, Westinghou ...

) * 1966 **

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) ** GEORGE 1 & 2 for ICT 1900 series ** Mod 1 ** Mod 2 ** Mod 8 ** MS/8 ( Richard F. Lary's DEC PDP-8 system) ** MSOS (Mass Storage Operating System) **

(IBM's primary OS for its S/360 series) PCP and MFT (''shipped'') ** RAX ** Remote Users of Shared Hardware (RUSH), a time-sharing system developed by Allen-Babcock for the IBM 360/50 ** SODA for

Elwro Elwro was a Polish company that manufactured mainframe and microcomputers from 1959 until 1989. Its plant was in Wrocław. Computer models included Odra (computer), Odra mainframe systems, and the List of ZX Spectrum clones#Elwro 800 Junior, Elwro ...

's Odra 1204 ** Universal Time-Sharing System ( XDS Sigma series) * 1967 ** CP-40, predecessor to CP-67 on modified IBM System/360 Model 40 **

CP-67 CP-67 is a hypervisor, or Virtual Machine Monitor, from IBM for its System/360 Model 67 computer. CP-67 is the control program portion of CP/CMS, a virtual machine operating system developed by IBM's Cambridge Scientific Center in Cambridge, ...

(IBM, also known as CP/CMS) **

Conversational Programming System Conversational Programming System or CPS is an early Time-sharing system offered by IBM which runs on System/360 mainframe computer, mainframes ''circa'' 1967 through 1972 in a partition of OS/360 Release 17 MFT II or MVT or above. CPS is imple ...

(CPS), an IBM time-sharing system under

Michigan Terminal System The Michigan Terminal System (MTS) is one of the first time-sharing computer operating systems.. Created in 1967 at the University of Michigan for use on IBM System/360, IBM S/360-67, S/370 and compatible mainframe computers, it was developed and ...

(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) ** OS/360 MVT ** 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) **

WAITS WAITS is a heavily modified variant of Digital Equipment Corporation's Monitor operating system (later renamed to, and better known as, " TOPS-10") for the PDP-6 and PDP-10 mainframe computers, used at the Stanford Artificial Intelligence Labor ...

(

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 b ...

, Stanford Artificial Intelligence Laboratory, time-sharing system for DEC PDP-6 and PDP-10, later TOPS-10) * 1968 ** Airline Control Program (ACP) (IBM) ** B1 (NCR Century series) ** CALL/360, an IBM time-sharing system for System/360 ** Real-Time Executive (RTE) – Hewlett-Packard **

(

Eindhoven University of Technology The Eindhoven University of Technology (), Abbreviation, abbr. TU/e, is a public university, public technical university in the Netherlands, situated in Eindhoven. In 2020–21, around 14,000 students were enrolled in its Bachelor of Science, BS ...

) publication ** TSS/8 (DEC for the PDP-8) ** VP/CSS * 1969 ** B2 (NCR Century series) ** B3 (NCR Century series) ** GEORGE 3 For ICL 1900 series **

(MIT, GE, Bell Labs for the

and later the

Honeywell 6180 The Honeywell 6000 series computers were a further development (using integrated circuits) of General Electric's 600-series mainframes manufactured by Honeywell International, Inc. from 1970 to 1989. Honeywell acquired the line when it purchas ...

) (''opened for paying customers in October'') ** RC 4000 Multiprogramming System ( RC) ** TENEX (

Bolt, Beranek and Newman Raytheon BBN (originally Bolt, Beranek and Newman, Inc.) is an American research and development company based in Cambridge, Massachusetts. In 1966, the Franklin Institute awarded the firm the Frank P. Brown Medal, in 1999 BBN received the ...

for DEC systems, later

TOPS-20 The TOPS-20 operating system by Digital Equipment Corporation (DEC) is a proprietary OS used on some of DEC's 36-bit mainframe computers. The Hardware Reference Manual was described as for "DECsystem-10/DECSYSTEM-20 Processor" (meaning the DEC PDP ...

) ** Unics (later Unix) (

AT&T AT&T Inc., an abbreviation for its predecessor's former name, the American Telephone and Telegraph Company, is an American multinational telecommunications holding company headquartered at Whitacre Tower in Downtown Dallas, Texas. It is the w ...

, initially on DEC computers) ** Xerox Operating System

1970s

* 1970 **

DOS-11 BATCH-11/DOS-11, also known simply as DOS-11, is a discontinued operating system by Digital Equipment Corporation (DEC) of Maynard, Massachusetts, Maynard, Massachusetts. The first version of DOS-11 (V08-02) was released in 1970 and was the first ...

(PDP-11) * 1971 ** EMAS ** Kronos ** RSTS-11 2A-19 (''First released version; PDP-11'') ** RSX-15 **

OS/8 OS/8 is the primary operating system used on the Digital Equipment Corporation's PDP-8 minicomputer. PDP-8 operating systems which precede OS/8 include: * R-L Monitor, also referred to as MS/8. * P?S/8, requiring only 4K of memory. * PDP-8 4K ...

* 1972 ** B4 (NCR Century series) ** COS-300 **

Data General RDOS The Data General RDOS (''Real-time Disk Operating System'') is a real-time operating system released in 1970. The software was bundled with the company's popular Nova and Eclipse minicomputers. Overview RDOS is capable of multitasking, with ...

** Edos ** MUSIC/SP ** OS/4 ** OS 1100 ** 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 t ...

(written in FORTRAN IV, that didn't have

pointers Pointer may refer to: People with the name * Pointer (surname), a surname (including a list of people with the name) * Pointer Williams (born 1974), American former basketball player Arts, entertainment, and media * ''Pointer'' (journal), the ...

, while later versions, around version 18, written in a version of

PL/I PL/I (Programming Language One, pronounced and sometimes written PL/1) is a procedural, imperative computer programming language initially developed by IBM. It is designed for scientific, engineering, business and system programming. It has b ...

, called PL/P) ** 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 ** CP-V (Control Program V) **

RSX-11 RSX-11 is a discontinued family of multi-user real-time operating systems for PDP-11 computers created by Digital Equipment Corporation. In widespread use through the late 1970s and early 1980s, RSX-11 was influential in the development of later ...

D **

RT-11 RT-11 (Real-time 11) is a discontinued small, low-end, single-user real-time operating system for the full line of Digital Equipment Corporation PDP-11 16-bit computers. RT-11 was first implemented in 1970. It was widely used for real-time compu ...

** VME – implementation language S3 (

ALGOL 68 ALGOL 68 (short for ''Algorithmic Language 1968'') is an imperative programming language member of the ALGOL family that was conceived as a successor to the ALGOL 60 language, designed with the goal of a much wider scope of application and ...

) * 1974 ** ACOS-2 (

NEC is a Japanese multinational information technology and electronics corporation, headquartered at the NEC Supertower in Minato, Tokyo, Japan. It provides IT and network solutions, including cloud computing, artificial intelligence (AI), Inte ...

) ** ACOS-4 ** ACOS-6 **

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/Intel 8085, 85-based microcomputers by Gary Kildall of Digital Research, Dig ...

V09-20C (''Last stable release, June 1974'') ** Hydra – capability-based, multiprocessing OS kernel ** MONECS ** Multi-Programming Executive (MPE) – Hewlett-Packard ** Operating System/Virtual Storage 2 R2 (MVS) ** OS/7 ** OS/16 ** OS/32 ** Sintran III * 1975 **

BS2000 BS2000 is an operating system for IBM 390-compatible mainframe computers developed in the 1970s by Siemens (Data Processing Department EDV) and from early 2000s onward by Fujitsu Technology Solutions. Unlike other mainframe systems, BS2000 prov ...

V2.0 (''First released version'') ** COS-350 **

ISIS Isis was a major goddess in ancient Egyptian religion whose worship spread throughout the Greco-Roman world. Isis was first mentioned in the Old Kingdom () as one of the main characters of the Osiris myth, in which she resurrects her sla ...

** NOS (Control Data Corporation) ** OS/3 (Univac) **

VS/9 VS/9 is a computer operating system for the UNIVAC Series 90 mainframes (90/60, 90/70, and 90/80), used during the late 1960s through 1980s. The 90/60 and 90/70 were repackaged Univac 9700 computers. After the RCA acquisition by Sperry, it ...

(formerly RCA's TSOS, later named VMOS) ** Version 6 Unix ** XVM/DOS ** XVM/RSX * 1976 ** Cambridge CAP computer – all operating system procedures written in

ALGOL 68C ALGOL 68C is an imperative computer programming language, a dialect of ALGOL 68, that was developed by Stephen R. Bourne and Michael Guy to program the Cambridge Algebra System (CAMAL). The initial compiler was written in the Princeton Synta ...

, 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 f ...

** Cray Operating System ** DX10 ** FLEX **

** TX990/TXDS ** Tandem Nonstop OS v1 **

Thoth Thoth (from , borrowed from , , the reflex of " eis like the ibis") is an ancient Egyptian deity. In art, he was often depicted as a man with the head of an African sacred ibis, ibis or a baboon, animals sacred to him. His feminine count ...

* 1977 ** 1BSD **

AMOS Amos or AMOS may refer to: Arts and entertainment * ''Amos'' (album), an album by Michael Ray * Amos (band), an American Christian rock band * ''Amos'' (film), a 1985 American made-for-television drama film * Amos (guitar), a 1958 Gibson Fl ...

KERNAL KERNAL is Commodore's name for the ROM-resident operating system core in its 8-bit home computers; from the original PET of 1977, followed by the extended but related versions used in its successors: the VIC-20, Commodore 64, Plus/4, Commodore ...

** OASIS operating system ** 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 ...

** RMX-80 ** System 88 (Exec) ** System Support Program (IBM System/34 and System/36) **

TRSDOS TRSDOS (which stands for the Tandy Radio Shack Disk Operating System) is the operating system for the Tandy TRS-80 line of eight-bit Zilog Z80 microcomputers that were sold through Radio Shack from 1977 through 1991. Tandy's manuals recommended ...

** Virtual Memory System (VMS) V1.0 (''Initial commercial release, October 25'') ** VRX (Virtual Resource eXecutive) ** VS Virtual Memory Operating System * 1978 ** 2BSD **

Apple DOS Apple DOS is the disk operating system for the Apple II computers 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 these three releases was foll ...

** Control Program Facility (IBM System/38) ** Cray Time Sharing System (CTSS) ** DPCX (IBM) ** DPPX (IBM) ** 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) ** OS4 (Naked Mini 4) ** PTDOS **

TRIPOS TRIPOS (''TRIvial Portable Operating System'') is a computer operating system. Development started in 1976 at the Computer Laboratory of Cambridge University and it was headed by Dr. Martin Richards. The first version appeared in January 1978 a ...

UCSD p-System UCSD Pascal is a Pascal (programming language), Pascal programming language system that runs on the UCSD p-System, a portable, highly machine-independent operating system. UCSD Pascal was first released in 1977. It was developed at the Universit ...

(''First released version'') * 1979 **

Atari DOS Atari DOS is the disk operating system used with the Atari 8-bit computers. Operating system extensions loaded into memory were required in order for an Atari computer to manage files stored on a disk drive. These extensions to the operat ...

** 3BSD ** CP-6 **

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 ...

MP/M MP/M (Multi-Programming Monitor Control Program) is a discontinued multi-user version of the CP/M operating system, created by Digital Research developer Tom Rolander in 1979. It allowed multiple users to connect to a single computer, each u ...

** MVS/System Extensions R2 (MVS/SE2) ** NLTSS ** POS **

Sinclair BASIC Sinclair BASIC is a dialect of the programming language BASIC used in the 8-bit home computers from Sinclair Research, Timex Sinclair and Amstrad. The Sinclair BASIC interpreter was written by Nine Tiles Networks Ltd. Designed to run in on ...

** Transaction Processing Facility (TPF) (IBM) ** UCLA Secure UNIX – an early secure UNIX OS based on security kernel ** UNIX/32V ** DOS/VSE **

Version 7 Unix Version 7 Unix, also called Seventh Edition Unix, Version 7 or just V7, was an important early release of the Unix operating system. V7, released in 1979, was the last Bell Laboratories release to see widespread distribution before the commerc ...

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 wi ...

** AOS/VS (Data General) ** Business Operating System ** CTOS ** 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-8 ...

OS-9 OS-9 is a family of real-time, process-based, multitasking, multi-user operating systems, developed in the 1980s, originally by Microware Systems Corporation for the Motorola 6809 microprocessor. It was purchased by Radisys Corp in 2001, a ...

** RMX-86 ** RS-DOS **

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

** Virtual Machine/System Product (VM/SP) **

Xenix Xenix is a discontinued Unix operating system for various microcomputer platforms, licensed by Microsoft from AT&T Corporation. The first version was released in 1980, and Xenix was the most common Unix variant during the mid- to late-1980s. T ...

* 1981 **

Acorn MOS The Machine Operating System (MOS) or OS is a discontinued computer operating system (OS) used in Acorn Computers' BBC computer range. It included support for four-channel sound, graphics, file system abstraction, and digital and analogue inp ...

Aegis The aegis ( ; ''aigís''), as stated in the ''Iliad'', is a device carried by Athena and Zeus, variously interpreted as an animal skin or a shield and sometimes featuring the head of a Gorgon. There may be a connection with a deity named Aex, a ...

SR1 (''First Apollo/DOMAIN systems shipped on March 27'') **

CP/M-86 CP/M-86 is a discontinued 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 Re ...

iMAX IMAX is a proprietary system of High-definition video, high-resolution cameras, film formats, film projectors, and movie theater, theaters known for having very large screens with a tall aspect ratio (image), aspect ratio (approximately ei ...

– OS for Intel's iAPX 432 capability machine ** MCS (Multi-user Control System) **

MS-DOS MS-DOS ( ; acronym for Microsoft Disk Operating System, also known as Microsoft DOS) is an operating system for x86-based personal computers mostly developed by Microsoft. Collectively, MS-DOS, its rebranding as IBM PC DOS, and a few op ...

PC DOS PC or pc may refer to: Arts and entertainment * Player character or playable character, a fictional character controlled by a human player, usually in role-playing games or computer games * '' Port Charles'', an American daytime TV soap opera * ...

Pilot An aircraft pilot or aviator is a person who controls the flight of an aircraft by operating its Aircraft flight control system, directional flight controls. Some other aircrew, aircrew members, such as navigators or flight engineers, are al ...

(''

Xerox Star The Xerox Star workstation, officially named Xerox Star 8010 Information System, is the first commercial personal computer to incorporate technologies that have since become standard in personal computers, including a bitmapped display, a window- ...

operating system'') ** UNOS ** UTS ** V ** VERSAdos ** VRTX ** VSOS (Virtual Storage Operating System) ** Xinu first release * 1982 ** Commodore DOS ** LDOS (By Logical Systems, Inc. – for the Radio Shack TRS-80 Models I, II & III) **

PCOS Polycystic ovary syndrome, or polycystic ovarian syndrome, (PCOS) is the most common endocrine disorder in women of reproductive age. The name is a misnomer, as not all women with this condition develop cysts on their ovaries. The name origi ...

(Olivetti M20) ** pSOS ** QNX **

Stratus VOS Stratus VOS (Virtual Operating System) is a proprietary operating system running on Stratus Technologies fault-tolerant computer systems. VOS is available on Stratus's ftServer and Continuum platforms. VOS customers use it to support high-volu ...

** Sun UNIX (later

SunOS SunOS is a Unix-branded operating system developed by Sun Microsystems for their workstation and server computer systems from 1982 until the mid-1990s. The ''SunOS'' name is usually only used to refer to versions 1.0 to 4.1.4, which were based ...

) 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 eq ...

** Unix System III ** VAXELN * 1983 **

Coherent Coherence is, in general, a state or situation in which all the parts or ideas fit together well so that they form a united whole. More specifically, coherence, coherency, or coherent may refer to the following: Physics * Coherence (physics ...

** DNIX **

EOS In ancient Greek mythology and Ancient Greek religion, religion, Eos (; Ionic Greek, Ionic and Homeric Greek ''Ēṓs'', Attic Greek, Attic ''Héōs'', "dawn", or ; Aeolic Greek, Aeolic ''Aúōs'', Doric Greek, Doric ''Āṓs'') is the go ...

GNU GNU ( ) is an extensive collection of free software (394 packages ), which can be used as an operating system or can be used in parts with other operating systems. The use of the completed GNU tools led to the family of operating systems popu ...

(''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 NetWare is a discontinued computer network operating system developed by Novell, Inc. It initially used cooperative multitasking to run various services on a personal computer, using the Internetwork Packet Exchange, IPX network protocol. The f ...

( S-Net) ** PERPOS **

ProDOS ProDOS is the name of two similar operating systems for the Apple II of personal computer. The original ProDOS, renamed ProDOS 8 in version 1.2, is the last official operating system usable by all 8-bit Apple II computers, and was distributed ...

** RTU (Real-Time Unix) ** STOP –

TCSEC Trusted Computer System Evaluation Criteria (TCSEC) is a United States Government Department of Defense (DoD) standard that sets basic requirements for assessing the effectiveness of computer security controls built into a computer system. The TC ...

A1-class, secure OS for SCOMP hardware **

1.0 ** VSE/System Package (VSE/SP) Version 1 * 1984 ** AMSDOS ** CTIX (Unix variant) **

DYNIX DYNIX (''DYNamic UnIX'') was a Unix-like operating system developed by Sequent Computer Systems, based on 4.2BSD and modified to run on Intel-based symmetric multiprocessor hardware. The third major (Dynix 3.0) version was released May, 1987; b ...

Mac OS Mac operating systems were developed by Apple Inc. in a succession of two major series. In 1984, Apple debuted the operating system that is now known as the classic Mac OS with its release of the original Macintosh System Software. The system ...

(''System 1.0'') **

MSX-DOS MSX-DOS is a discontinued disk operating system developed by Microsoft's Japan subsidiary for the 8-bit home computer standard MSX, and is a cross between MS-DOS v1.25 and CP/M-80 v2.2. MSX-DOS MSX-DOS and the extended BASIC with 3½-in ...

** NOS/VE ** PANOS ** PC/IX ** ROS ** Sinclair QDOS ** QNX ** SINIX ** UNICOS **

Venix Venix is a discontinued version of the Unix operating system for low-end computers, developed by VenturCom, a "company that specialises in the skinniest implementations of Unix".VenturCom ships real-time Venix/386. Computer Business Review, 1 F ...

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

AmigaOS AmigaOS is a family of proprietary native operating systems of the Amiga and AmigaOne personal computers. It was developed first by Commodore International and introduced with the launch of the first Amiga, the Amiga 1000, in 1985. Early versions ...

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 DOS Plus (erroneously also known as DOS+) was the first operating system developed by Digital Research's OEM Support Group in Newbury, Berkshire, UK, first released in 1985. DOS Plus 1.0 was based on CP/M-86 Plus combined with the PCM ...

** Graphics Environment Manager **

Harmony In music, harmony is the concept of combining different sounds in order to create new, distinct musical ideas. Theories of harmony seek to describe or explain the effects created by distinct pitches or tones coinciding with one another; harm ...

** MIPS RISC/os **

Oberon Oberon () is a king of the fairy, fairies in Middle Ages, medieval and Renaissance literature. He is best known as a character in William Shakespeare's play ''A Midsummer Night's Dream'', in which he is King of the Fairies and spouse of Titania ...

– written in

2.0 ** Version 8 Unix ** Virtual Machine/Extended Architecture System Facility (VM/XA SF) ** Windows 1.0 ** Windows 1.01 **

2.0 * 1986 ** AIX 1.0 ** Cronus distributed OS **

FlexOS FlexOS is a discontinued modular real-time multiuser multitasking operating system ( RTOS) designed for computer-integrated manufacturing, laboratory, retail and financial markets. Developed by Digital Research's Flexible Automation Business ...

** GEMSOS –

A1-class, secure kernel for BLACKER VPN & GTNP ** GEOS **

Genera Genus (; : genera ) is a taxonomic rank above species and below family as used in the biological classification of living and fossil organisms as well as viruses. In binomial nomenclature, the genus name forms the first part of the binomial s ...

7.0 **

HP-UX HP-UX (from "Hewlett Packard Unix") is a proprietary software, proprietary implementation of the Unix operating system developed by Hewlett Packard Enterprise; current versions support HPE Integrity Servers, based on Intel's Itanium architect ...

3.0 ** TR-DOS ** TRIX ** Version 9 Unix * 1987 **

Arthur Arthur is a masculine given name of uncertain etymology. Its popularity derives from it being the name of the legendary hero King Arthur. A common spelling variant used in many Slavic, Romance, and Germanic languages is Artur. In Spanish and Ital ...

(much improved version came in 1989 under the name

RISC OS RISC OS () is an operating system designed to run on ARM architecture, ARM computers. Originally designed in 1987 by Acorn Computers of England, it was made for use in its new line of ARM-based Acorn Archimedes, Archimedes personal computers an ...

) **

V9.0 **

IRIX IRIX (, ) is a discontinued operating system developed by Silicon Graphics (SGI) to run on the company's proprietary MIPS architecture, MIPS workstations and servers. It is based on UNIX System V with Berkeley Software Distribution, BSD extensio ...

(''3.0 is first SGI version'') ** MDOS **

MINIX MINIX is a Unix-like operating system based on a microkernel Software architecture, architecture, first released in 1987 and written by American-Dutch computer scientist Andrew S. Tanenbaum. It was designed as a clone of the Unix operating syste ...

1.0 **

OS/2 OS/2 is a Proprietary software, proprietary computer operating system for x86 and PowerPC based personal computers. It was created and initially developed jointly by IBM and Microsoft, under the leadership of IBM software designer Ed Iacobucci, ...

(1.0) **

PC-MOS/386 PC-MOS/386 is a multi-user, multitasking computer operating system produced by The Software Link (TSL), announced at COMDEX in November 1986 for February 1987 release. PC-MOS/386, a successor to PC-MOS, can run many MS-DOS programs on the host ...

** Topaz – semi-distributed OS for DEC Firefly workstation written in Modula-2+ and garbage collected ** Windows 2.0 * 1988 **

A/UX A/UX is a Unix-based operating system from Apple Computer for Macintosh computers, integrated with System 7's graphical interface and application compatibility. It is Apple's first official Unix-based operating system, launched in 1988 and disc ...

(Apple Computer) ** AOS/VS II (Data General) **

rebranded as

DR-DOS DR-DOS is a disk operating system for IBM PC compatibles, originally developed by Gary A. Kildall's Digital Research, Inc. and derived from Concurrent PC DOS 6.0, which was an advanced successor of CP/M-86. Upon its introduction in 198 ...

Flex machine The Flex Computer System was developed by Michael Foster and Ian Currie of Royal Signals and Radar Establishment (RSRE) in Malvern, England, during the late 1970s and 1980s. It used a tagged storage scheme to implement a capability architect ...

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

HeliOS In ancient Greek religion and Greek mythology, mythology, Helios (; ; Homeric Greek: ) is the god who personification, personifies the Sun. His name is also Latinized as Helius, and he is often given the epithets Hyperion ("the one above") an ...

1.0 **

KeyKOS KeyKOS is a persistent, pure capability-based operating system for the IBM S/370 mainframe computers. It allows emulating the environments of VM, MVS, and Portable Operating System Interface (POSIX). It is a predecessor of the Extremely Reli ...

– capability-based microkernel for IBM mainframes with automated persistence of app data **

LynxOS The LynxOS RTOS is a Unix-like real-time operating system from Lynx Software Technologies (formerly "LynuxWorks"). Sometimes known as the Lynx Operating System, LynxOS features full POSIX conformance and, more recently, Linux compatibility. L ...

('' System 6'') ** MVS/System Product V3 (MVS/Enterprise Systems Architecture, MVS/ESA) **

(1.1) **

OS/400 IBM i (the ''i'' standing for ''integrated'') is an operating system developed by IBM for IBM Power Systems. It was originally released in 1988 as OS/400, as the sole operating system of the IBM AS/400 line of systems. It was renamed to i5/OS in 2 ...

RISC iX RISC iX is a discontinued Unix operating system designed to run on a series of workstations based on the Acorn Archimedes microcomputer. Heavily based on 4.3BSD, it was initially completed in 1988, a year after Arthur but before RISC OS. It was ...

SpartaDOS X SpartaDOS X (or SpartaDOS 4.0) is a disk operating system for the Atari 8-bit computers that closely resembles MS-DOS. It was developed and sold by ICD in 1987-1993, and many years later picked up by the third-party community SpartaDOS X Upgrade ...

4.0 **

7.04 (''Last stable release, July 1988'') ** Virtual Machine/Extended Architecture System Product (VM/XA SP) ** VAX VMM –

A1-class, VMM for

VAX VAX (an acronym for virtual address extension) is a series of computers featuring a 32-bit instruction set architecture (ISA) and virtual memory that was developed and sold by Digital Equipment Corporation (DEC) in the late 20th century. The V ...

computers (limited use before cancellation) * 1989 ** Army Secure Operating System (ASOS) –

A1-class secure, real-time OS for Ada applications ** EPOC (EPOC16) **

NeXTSTEP NeXTSTEP is a discontinued object-oriented, multitasking operating system based on the Mach kernel and the UNIX-derived BSD. It was developed by NeXT, founded by Steve Jobs, in the late 1980s and early 1990s and was initially used for its ...

(1.0) **

(1.2) **

(''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 Xinuos OpenServer, previously SCO UNIX and SCO Open Desktop (SCO ODT), is a closed source computer operating system developed by Santa Cruz Operation (SCO), later acquired by SCO Group, and now owned by Xinuos. Early versions of OpenServer were ...

(''Release 3'') **

TSX-32 TSX-32 is a discontinued general purpose 32-bit multi-user multitasking operating system for the x86 architecture platform, with a command line user interface. It is compatible with some 16-bit DOS applications and supports the FAT16 and FA ...

** Version 10 Unix **

2.3.4 (''Last stable release'')

1990s

* 1990 ** AIX 3.0 **

2.0 **

BeOS BeOS is a discontinued operating system for personal computers that was developed by Be Inc. It was conceived for the company's BeBox personal computer which was released in 1995. BeOS was designed for multitasking, multithreading, and a graph ...

(v1) **

DOS/V DOS/V is a Japanese computing initiative starting in 1990 to allow DOS on IBM PC compatibles with VGA cards to handle Double-byte character set, double-byte (DBCS) Japanese text via software alone. It was initially developed from PC DOS by IBM f ...

8.0 ** iS-DOS ** LOCK –

A1-class secure system with kernel and hardware support for type enforcement ** MVS/ESA SP Version 4 **

3 **

1.3 ** OSF/1 ** RTEMS **

PC/GEOS GEOS (later renamed GeoWorks Ensemble, NewDeal Office, and Breadbox Ensemble) is a computer operating environment, graphical user interface (GUI), and suite of application software. Originally released as PC/GEOS, it runs on MS-DOS-based, I ...

** Windows 3.0 ** Virtual Machine/Enterprise Systems Architecture (VM/XA ESA) ** VSE/Enterprise Systems Architecture (VSE/ESA) Version 1 * 1991 **

Amoeba An amoeba (; less commonly spelled ameba or amœba; : amoebas (less commonly, amebas) or amoebae (amebae) ), often called an amoeboid, is a type of Cell (biology), cell or unicellular organism with the ability to alter its shape, primarily by ...

– microkernel-based, POSIX-compliant, distributed OS ** GNO/ME **

Linux Linux ( ) is a family of open source Unix-like operating systems based on the Linux kernel, an kernel (operating system), operating system kernel first released on September 17, 1991, by Linus Torvalds. Linux is typically package manager, pac ...

0.01-0.1 **

(''

System 7 System 7 (later named Mac OS 7) is the seventh major release of the classic Mac OS operating system for Macintosh computers, made by Apple Computer. It was launched on May 13, 1991, to succeed System 6 with virtual memory, personal file shari ...

'') **

1.5 ** PenPoint OS **

3 ** SUNMOS ** Trusted Xenix – rewritten & security enhanced Xenix evaluated at

B2-class * 1992 **

386BSD 386BSD (also known as "Jolix") is a Unix-like operating system that was developed by couple Lynne and William "Bill" Jolitz. Released as free and open source in 1992, it was the first fully operational Unix built to run on IBM PC-compatible s ...

0.1 ** Amiga Unix 2.01 (''Latest stable release'') **

3.0 ** BSD/386, by BSDi 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 Op ...

V1.0 (''First OpenVMS AXP (Alpha) specific version, November 1992'') **

2.0 (First i386 32-bit based version) ** Plan 9 First Edition (''First public release was made available to universities'') **

RSTS/E 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 ...

10.1 (''Last stable release, September 1992'') ** SLS **

Solaris Solaris is the Latin word for sun. It 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 ** ''Sol ...

2.0 (''Successor to SunOS 4.x; based on SVR4 instead of BSD'') **

Windows 3.1 Windows 3.1 is a major release of Microsoft Windows. It was released to manufacturing on April 6, 1992, as a successor to Windows 3.0. Like its predecessors, the Windows 3.1 series run as a shell on top of MS-DOS; it was the last Windows 1 ...

* 1993 ** IBM 4690 Operating System **

FreeBSD FreeBSD is a free-software Unix-like operating system descended from the Berkeley Software Distribution (BSD). The first version was released in 1993 developed from 386BSD, one of the first fully functional and free Unix clones on affordable ...

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

4 **

Newton OS ''Newton OS'' is a discontinued operating system for the Apple Newton PDAs produced by Apple Computer, Inc. between 1993 and 1997. It was written entirely in C++ and trimmed to be low power consuming and use the available memory efficiently. Ma ...

Nucleus RTOS Nucleus RTOS is a real-time operating system (RTOS) produced by the Embedded Software Division of Mentor Graphics, a Siemens Business, supporting 32-bit computing, 32- and 64-bit computing, 64-bit embedded system platforms. The operating system (O ...

** Open Genera 1.0 ** OS 2200 (

Unisys Unisys Corporation is a global technology solutions company founded in 1986 and headquartered in Blue Bell, Pennsylvania. The company provides cloud, AI, digital workplace, logistics, and enterprise computing services. History Founding Unis ...

) **

2.1 **

PTS-DOS PTS-DOS (aka PTS/DOS) is a disk operating system, a DOS clone, developed in Russia by PhysTechSoft and Paragon Technology Systems. History and versions PhysTechSoft was formed in 1991 in Moscow, Russia by graduates and members of MIPT, inf ...

Slackware Slackware is a Linux distribution created by Patrick Volkerding in 1993. Originally based on Softlanding Linux System (SLS), Slackware has been the basis for many other Linux distributions, most notably the first versions of SUSE Linux distr ...

1.0 ** Spring **

Windows NT 3.1 Windows NT 3.1 is the first major release of the Windows NT operating system developed by Microsoft, released on July 27, 1993. It marked the company's entry into the corporate computing environment, designed to support large networks and to be ...

(''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'') **

Warp 3.0 **

Red Hat Red Hat, Inc. (formerly Red Hat Software, Inc.) is an American software company that provides open source software products to enterprises and is a subsidiary of IBM. Founded in 1993, Red Hat has its corporate headquarters in Raleigh, North ...

3.5 **

SPIN Spin or spinning most often refers to: * Spin (physics) or particle spin, a fundamental property of elementary particles * Spin quantum number, a number which defines the value of a particle's spin * Spinning (textiles), the creation of yarn or thr ...

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

OpenBSD OpenBSD is a security-focused operating system, security-focused, free software, Unix-like operating system based on the Berkeley Software Distribution (BSD). Theo de Raadt created OpenBSD in 1995 by fork (software development), forking NetBSD ...

** OS/390 ** Plan 9 Second Edition (''Commercial second release version was made available to the general public.'') ** SMSQ/E **

4.5 (''Last major release'') **

Windows 95 Windows 95 is a consumer-oriented operating system developed by Microsoft and the first of its Windows 9x family of operating systems, released to manufacturing on July 14, 1995, and generally to retail on August 24, 1995. Windows 95 merged ...

* 1996 ** AIX 4.2 **

Debian Debian () is a free and open-source software, free and open source Linux distribution, developed by the Debian Project, which was established by Ian Murdock in August 1993. Debian is one of the oldest operating systems based on the Linux kerne ...

1.1 ** JN – microkernel OS for embedded, Java apps ** Mac OS 7.6 (''First officially-named Mac OS'') **

Warp 4.0 **

Palm OS Palm OS (also known as Garnet OS) is a discontinued mobile operating system initially developed by Palm, Inc., for personal digital assistants (PDAs) in 1996. Palm OS was designed for ease of use with a touchscreen-based graphical user interface. ...

3.6 ** Windows NT 4.0 ** Windows CE 1.0 * 1997 ** AIX 4.3 ** DR-WebSpyder 1.0 ** EPOC (EPOC32) ** Inferno **

Mac OS 8 Mac OS 8 is the eighth major release of the classic Mac OS operating system for Macintosh computers, released by Apple Computer on July 26, 1997. It includes the largest overhaul of the classic Mac OS experience since the release of System 7 ...

2.0 **

Nemesis In ancient Greek religion and myth, Nemesis (; ) also called Rhamnousia (or Rhamnusia; ), was the goddess who personified retribution for the sin of hubris: arrogance before the gods. Etymology The name ''Nemesis'' is derived from the Greek ...

3.7 ** SkyOS ** Windows CE 2.0 * 1998 ** DR-WebSpyder 2.0 ** Junos **

5 **

5.7 (''Last stable release, October 1998'') **

7 (''first

64-bit In computer architecture, 64-bit integers, memory addresses, or other data units are those that are 64 bits wide. Also, 64-bit central processing units (CPU) and arithmetic logic units (ALU) are those that are based on processor registers, a ...

Solaris release – names from this point drop "2.", otherwise would've been Solaris 2.7'') **

Windows 98 Windows 98 is a consumer-oriented operating system developed by Microsoft as part of its Windows 9x family of Microsoft Windows operating systems. It was the second operating system in the 9x line, as the successor to Windows 95. It was Software ...

* 1999 ** Amiga OS 3.5 ''(unofficial)'' ** 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 and final major release of the classic Mac OS operating system for Macintosh computers, made by Apple Computer. Introduced on October 23, 1999, it was promoted by Apple as "The Best Internet Operating System Ever", highlight ...

Warp 4.5 **

4 ** Windows 98 (2nd edition)

2000s

2010s

2020s

References

External links

UNIX History
– a timeline of

UNIX Unix (, ; trademarked as UNIX) is a family of multitasking, multi-user computer operating systems that derive from the original AT&T Unix, whose development started in 1969 at the Bell Labs research center by Ken Thompson, Dennis Ritchie, a ...

1969 and its descendants at present
Concise Microsoft O.S. Timeline
– a color-coded concise timeline for various Microsoft operating systems (1981–present)
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 and software resources, and provides common daemon (computing), services for computer programs. Time-sharing operating systems scheduler (computing), schedule tasks for ...

Real-time operating systems A real-time operating system (RTOS) is an operating system (OS) for real-time computing applications that processes data and events that have critically defined time constraints. A RTOS is distinct from a time-sharing operating system, such as Unix ...

Embedded operating systems An embedded operating system (EOS) is an operating system designed specifically for embedded computer systems. These systems aim to enhance functionality and reliability to perform dedicated tasks. When the multitasking method employed allows ...

1950s

1960s

1970s

1980s

1990s

2000s

2010s

2020s

See also

References

External links