Timeline of operating systems

• 1951
• LEO I 'Lyons Electronic Office'{{cite web|url=https://www.bbc.co.uk/dna/h2g2/A1000729|title=h2g2 - Early Electronic Computers - Edited Entry|author=Not Panicking Ltd|date=January 7, 2012|access-date=March 15, 2015}} was the commercial development of EDSAC computing platform, supported by British firm J. Lyons and Co.
• 1953
• DYSEAC - an early machine capable of distributing computing
• 1955
• General Motors Operating System made for IBM 701{{cite web|url=http://www.csee.wvu.edu/~jdm/classes/cs258/OScat/early.html|title=Early Operating Systems|access-date=March 15, 2015|url-status=dead|archive-url=https://web.archive.org/web/20150410053229/http://www.csee.wvu.edu/~jdm/classes/cs258/OScat/early.html|archive-date=April 10, 2015|df=mdy-all}}
• MIT's Tape Director operating system made for UNIVAC 1103{{cite web|url=http://www.csail.mit.edu/timeline/timeline.php/timeline.php?query=event&id=3|title=LCS/AI Lab Timeline|access-date=March 15, 2015|archive-url=https://web.archive.org/web/20150923211552/http://www.csail.mit.edu/timeline/timeline.php/timeline.php?query=event&id=3|archive-date=September 23, 2015|url-status=dead|df=mdy-all}}{{cite book |last1=Ross |first1=Douglas |chapter=A personal view of the personal work station: Some firsts in the Fifties |title=Proceedings of the ACM Conference on the history of personal workstations |date=9 January 1986 |pages=19–48 |doi=10.1145/12178.12180|publisher=Association for Computing Machinery|isbn=0-89791-176-8 |author-link=Douglas T. Ross}}
• 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

• 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) for B5000

• 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
• ADMIRAL{{cite web|url=http://www.bitsavers.org/pdf/honeywell/h1800/HONEYWELL_1800-II_A_Large-Scale_Scientific_Processor_1963.pdf |title=Honeywell 1800-II: A Large-Scale Scientific Processor |publisher=Honeywell |access-date=2024-03-27}}
• 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
• Berkeley Timesharing System (for Scientific Data Systems' SDS 940)
• Chippewa Operating System (for CDC 6600 supercomputer)
• Dartmouth Time-Sharing System (Dartmouth College's DTSS for GE computers)
• EXEC 8 (UNIVAC)
• 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)
• OS/360 (IBM's primary OS for its S/360 series) (announced)
• PDP-6 Monitor (DEC) descendant renamed TOPS-10 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 (MIT, GE, Bell Labs for the GE-645) (announced)
• Pick operating system
• SIPROS 66 (Simultaneous Processing Operating System){{cite web|url=http://bitsavers.org/pdf/cdc/cyber/cyber_70/sipros/60101800A_SIPROS66ref_1965.pdf |title=CONTROL DATA® 6600 Computer System – Operating System/Reference Manual – SIPROS 66 |publisher=Control Data Corp. |access-date=2024-03-28}}
• THE multiprogramming system (Technische Hogeschool Eindhoven) development
• TSOS (later VMOS) (RCA)
• 1966
• DOS/360 (IBM's Disk Operating System)
• GEORGE 1 & 2 for ICT 1900 series
• Mod 1{{cite web|url=http://www.bitsavers.org/pdf/honeywell/series200/charlie_gibbs/012_Series_200_Summary_Description.pdf |title=Honeywell Series 200 - Summary Description |publisher=Honeywell |access-date=2024-03-27}}
• Mod 2{{cite web|url=https://bitsavers.org/pdf/honeywell/series200/charlie_gibbs/393_Introduction_to_Operating_System_-_Mod_2.pdf |title=Introduction to Series 200/0perating System - Mod 2 |publisher=Honeywell |access-date=2024-03-27}}
• Mod 8{{cite web|url=http://s3data.computerhistory.org/brochures/honeywell.osorientationmgmt.1966.102646090.pdf |title=Operating System Orientation for Management - Series 200 Operating System In Review |publisher=Honeywell |access-date=2024-03-27}}
• MS/8 (Richard F. Lary's DEC PDP-8 system)
• MSOS (Mass Storage Operating System){{cite web|url=http://bitsavers.org/pdf/cdc/3x00/24bit/msos/60174100A_3100_3200_3300_3500_Mass_Storage_Sort_MSOS_Sep1967.pdf |title=3100 3200 3300 3500 Computer Systems – Mass Storage Sort/MSOS (Reference Manual) |publisher=Control Data Corp. |access-date=2024-03-28}}
• OS/360 (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'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 (IBM, also known as CP/CMS)
• Conversational Programming System (CPS), an IBM time-sharing system under OS/360
• Michigan Terminal System (MTS){{cite web|url=http://www.clock.org/~jss/work/mts/timeline.html |title=Michigan Terminal System: Time Line |publisher=Clock.org |access-date=2012-10-19}} (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 (SAIL, 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){{Cite web|url=http://www.bitsavers.org/pdf/ncr/NCR_DataPro_Reports/70C-656-01_7208_NCR_Century_Series.pdf|title=25 Years of Real-Time Computing by Todd Poynor|website=bitsavers.org|date=August 1991|access-date=June 24, 2024}}
• CALL/360, an IBM time-sharing system for System/360
• Real-Time Executive (RTE) – Hewlett-Packard{{Cite web|url=http://www.bitsavers.org/pdf/hp/21xx/poyner1.htm|title=25 Years of Real-Time Computing by Todd Poynor|website=bitsavers.org|date=August 1, 1972|access-date=July 16, 2024}}
• THE multiprogramming system (Eindhoven University of Technology) publication
• TSS/8 (DEC for the PDP-8)
• VP/CSS
• 1969
• B2 (NCR Century series){{Cite web|url=http://www.bitsavers.org/pdf/ncr/NCR_DataPro_Reports/70C-656-01_7601_NCR_Century_Series.pdf|title=Datapro – NCR Century Series (70C-656-01a Computers)|website=bitsavers.org|access-date=June 24, 2024}}
• B3 (NCR Century series)
• GEORGE 3 For ICL 1900 series
• Multics (MIT, GE, Bell Labs for the GE-645 and later the Honeywell 6180) (opened for paying customers in October{{cite web|url=http://www.multicians.org/history.html|title=Multics History|access-date=March 15, 2015}})
• RC 4000 Multiprogramming System (RC)
• TENEX (Bolt, Beranek and Newman for DEC systems, later TOPS-20)
• Unics (later Unix) (AT&T, initially on DEC computers)
• Xerox Operating System

• 1970
• DOS-11 (PDP-11)
• 1971
• EMAS
• Kronos
• RSTS-11 2A-19 (First released version; PDP-11)
• RSX-15
• OS/8
• 1972
• B4 (NCR Century series)
• COS-300
• Data General RDOS
• Edos
• MUSIC/SP
• OS/4
• OS 1100
• Operating System/Virtual Storage 1 (OS/VS1)
• Operating System/Virtual Storage 2 R1 (OS/VS2 SVS)
• 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)
• 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-11D
• RT-11
• VME – implementation language S3 (ALGOL 68)
• 1974
• ACOS-2 (NEC)
• ACOS-4
• ACOS-6
• CP/M{{Cite web |url=http://www.digitalresearch.biz/CPM.HTM |title=Digital Research home page |access-date=September 27, 2021 }}
• DOS-11 V09-20C (Last stable release, June 1974)
• Hydra{{Cite journal

| journal = Communications of the ACM | title = HYDRA:The Kernel of a Multiprocessor Operating System | date = June 1974 | volume = 17 | number = 6 | first1 = W. | last1 = Wulf | first2 = E. | last2 = Cohen | first3 = W. | last3 = Corwin | first4 = A. | last4 = Jones | first5 = R. | last5 = Levin | first6 = C. | last6 = Pierson | first7 = F. | last7 = Pollack | doi = 10.1145/355616.364017 | s2cid = 8011765 | url= https://www.cs.virginia.edu/people/faculty/pdfs/p337-wulf.pdf | archive-url = https://web.archive.org/web/20140503035517/https://www.cs.virginia.edu/people/faculty/pdfs/p337-wulf.pdf | archive-date = May 3, 2014 | url-status= dead | df= mdy-all | access-date = March 26, 2023}} – 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 V2.0 (First released version)
• COS-350{{Cite magazine|date=30 July 1975|title=Time-Sharing Uses Emphasized For DEC Datasystem 350 Series|url=https://books.google.com/books?id=jT2fQqJplN8C&pg=PT29|magazine=Computerworld|publisher=Computerworld, Inc.|access-date=7 March 2023}}
• ISIS
• NOS (Control Data Corporation)
• OS/3 (Univac)
• VS/9 (formerly RCA's TSOS, later named VMOS)
• Version 6 Unix
• XVM/DOS
• XVM/RSX
• 1976
• Cambridge CAP computer{{Cite book

| url = https://www.microsoft.com/en-us/research/publication/the-cambridge-cap-computer-and-its-operating-system/

| title = The Cambridge CAP Computer and Its Operating System

| first1 = M. V.

| last1 = Wilkes

| first2 = R. M.

| last2 = Needham

| editor-first = Peter J.

| editor-last = Denning

| date = January 1, 1979

| series = Operating and Programming Systems Series

| publisher = North Holland

| via = www.microsoft.com

| access-date = March 26, 2023

}}

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

• Cray Operating System
• DX10
• FLEX{{cite web|url=http://www.flexusergroup.com/flexusergroup/fug3.htm|title=FLEX User Group - History|author=Ian P. Blythe|access-date=March 15, 2015}}
• TOPS-20
• TX990/TXDS
• Tandem Nonstop OS v1
• Thoth
• 1977
• 1BSD
• AMOS
• KERNAL
• OASIS operating system
• OS68
• OS4000
• RMX-80
• System 88 (Exec)
• System Support Program (IBM System/34 and System/36)
• TRSDOS
• Virtual Memory System (VMS) V1.0 (Initial commercial release, October 25)
• VRX (Virtual Resource eXecutive)
• VS Virtual Memory Operating System{{Cite web|url=https://bitsavers.org/pdf/wang/vs/800-1107OS-03_VS_Operating_System_Services_198708.pdf|title=Wang – Operating System Services|website=bitsavers.org|access-date=June 24, 2024}}
• 1978
• 2BSD
• Apple DOS
• Control Program Facility (IBM System/38)
• Cray Time Sharing System (CTSS)
• DPCX (IBM)
• DPPX (IBM)
• HDOS
• KSOS{{cite web |url=http://csrc.nist.gov/publications/history/ford78.pdf |title= SECURE MINICOMPUTER OPERATING SYSTEM (KSOS) |website=csrc.nist.gov |access-date=2020-09-14}} – secure OS design from Ford Aerospace
• KVM/370{{Cite web |url=http://www.cs.washington.edu/research/projects/poirot3/Oakland/sp/PAPERS/00044538.PDF |title=KVM/370 IN RETROSPECT | first1=B. D. |last1=Gold |first2=R. R |last2=Linde |first3=P. F. |last3=Cudney |access-date=May 2, 2014 |archive-url=https://web.archive.org/web/20140503014429/http://www.cs.washington.edu/research/projects/poirot3/Oakland/sp/PAPERS/00044538.PDF |archive-date=May 3, 2014 |url-status=dead |df=mdy-all }} – security retro-fit of IBM VM/370
• Lisp machine (CADR)
• MVS/System Extensions (MVS/SE)
• OS4 (Naked Mini 4)
• PTDOS{{cite web|url=http://www.hartetechnologies.com/manuals/Processor%20Technology/Solus%20News/proteus_v1n1.pdf|title=SOLUS NEWS|editor=Stan Sokolow|access-date=January 30, 2020}}
• TRIPOS
• UCSD p-System (First released version)
• 1979
• Atari DOS
• 3BSD
• CP-6
• Idris
• MP/M
• MVS/System Extensions R2 (MVS/SE2)
• NLTSS
• POS
• Sinclair BASIC
• Transaction Processing Facility (TPF) (IBM)
• UCLA Secure UNIX{{Cite web|url=https://www.computer.org/csdl/proceedings-article/afips/1979/50870355/12OmNzcPAEy|title=CSDL | IEEE Computer Society|website=www.computer.org}} – an early secure UNIX OS based on security kernel
• UNIX/32V
• DOS/VSE
• Version 7 Unix

• 1980
• 86-DOS
• AOS/VS (Data General)
• Business Operating System
• CTOS{{cite web |url=http://www.byte.com/art/9412/sec13/art2.htm|archive-url=https://web.archive.org/web/20080828190425/http://www.byte.com/art/9412/sec13/art2.htm |archive-date=August 28, 2008|title=CTOS Revealed|author1=Dirk S. Faegre |author2=Jon Udell|date=December 1994 |publisher=BYTE.com|url-status=dead}}
• MVS/System Product (MVS/SP) V1
• NewDos/80
• OS-9
• RMX-86
• RS-DOS
• SOS
• Virtual Machine/System Product (VM/SP)
• Xenix
• 1981
• Acorn MOS
• Aegis SR1 (First Apollo/DOMAIN systems shipped on March 27{{cite web|url=http://www.zepa.net/apollo/|title=Apollo/DOMAIN Computers|access-date=March 15, 2015}})
• CP/M-86
• iMAX – OS for Intel's iAPX 432 capability machine
• MCS (Multi-user Control System)
• MS-DOS
• PC DOS
• Pilot (Xerox Star operating system)
• UNOS
• UTS
• V
• VERSAdos{{cite web|url=https://vintageapple.org/byte/pdf/198106_Byte_Magazine_Vol_06-06_Operating_Systems.pdf |title=Byte (magazine) |date=1981-06-01 |access-date=2024-03-29}}
• VRTX
• VSOS (Virtual Storage Operating System){{cite web|url=https://docs.lib.purdue.edu/cgi/viewcontent.cgi?article=1376&context=cstech |title=Implemeting a scalar C compiler on the Cyber 205 |last1=Li |first1=Kuo-Cheng |last2=Schwetman |first2=Herb |publisher=Purdue University |date=1983-10-06 |access-date=2024-03-28}}
• Xinu first release
• 1982
• Commodore DOS
• LDOS (By Logical Systems, Inc. – for the Radio Shack TRS-80 Models I, II & III)
• PCOS (Olivetti M20)
• pSOS
• QNX
• Stratus VOS{{cite web |url=http://ftp.stratus.com:80/vos/doc/reference/machine_history.txt |last=Green |first=Paul |date=20 May 2002 |title=Stratus Machine History |website=ftp.stratus.com:80 |access-date=13 January 2022 |archive-url=https://web.archive.org/web/20030612194052/http://ftp.stratus.com:80/vos/doc/reference/machine_history.txt |archive-date=12 June 2003 |url-status=dead}}
• Sun UNIX (later SunOS) 0.7
• Ultrix
• Unix System III
• VAXELN
• 1983
• Coherent
• DNIX
• EOS
• GNU (project start)
• Lisa Office System 7/7
• LOCUS{{cite tech report |last1=Walker |first1=Bruce |last2=Popek |first2=Gerald |last3=English |first3=Robert |last4=Kline |first4=Charles |last5=Thiel |first5=Greg |date= |title=The LOCUS Distributed Operating System |institution=University of California at Los Angeles |number= |url=https://pages.cs.wisc.edu/~bart/736/papers/locus.pdf }} – UNIX compatible, high reliability, distributed OS
• MVS/System Product V2 (MVS/Extended Architecture, MVS/XA)
• Novell NetWare (S-Net)
• PERPOS
• ProDOS
• RTU (Real-Time Unix)
• STOP{{cite web |url=http://apps.dtic.mil/dtic/tr/fulltext/u2/a229523.pdf |archive-url=https://web.archive.org/web/20150924072244/http://www.dtic.mil/dtic/tr/fulltext/u2/a229523.pdf |url-status=live |archive-date=September 24, 2015 |title=FINAL EVALUATION REPORTM OFN SCOMP |date=1965 |website=www.dtic.mil |access-date=2020-09-14}} – TCSEC A1-class, secure OS for SCOMP hardware
• SunOS 1.0
• VSE/System Package (VSE/SP) Version 1{{cite web

| title = NEW VSE SYSTEM IPO/E 1.4.0 AND VSE/SYSTEM PACKAGE 1.1.0

| id = LTR 283-217

| date = July 19, 1983

| url = https://www.ibm.com/common/ssi/ShowDoc.wss?docURL=/common/ssi/rep_ca/7/897/ENUS283-217/index.html

| work = Announcement Letters

| publisher = IBM

| access-date = March 26, 2023

}}

• 1984
• AMSDOS
• CTIX (Unix variant)
• DYNIX
• Mac OS (System 1.0)
• MSX-DOS
• NOS/VE{{cite web|url=https://www.uwyo.edu/infotech/aboutit/history/cyber-era.asp |title=University of Wyoming – Information Technology: About IT: History – The Cyber Era |access-date=2024-03-28}}{{cite web|url=https://www.youtube.com/watch?v=HvLlfXZMBXg |title=Westinghouse & Control Data Corporation - NOS/VE (1984) |date=July 17, 2011 |publisher=Westinghouse |access-date=2024-03-28}}
• PANOS
• PC/IX
• ROS
• Sinclair QDOS
• QNX
• SINIX
• UNICOS
• Venix 2.0
• Virtual Machine/Extended Architecture Migration Assistance (VM/XA MA)
• 1985
• AmigaOS
• Atari TOS
• DG/UX
• DOS Plus
• Graphics Environment Manager
• Harmony
• MIPS RISC/os
• Oberon – written in Oberon
• SunOS 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 OSVinter, S. T. and Schantz, R. E. 1986. The Cronus distributed operating system. In Proceedings of the 2nd Workshop on Making Distributed Systems Work (Amsterdam, Netherlands, September 8–10, 1986). EW 2. ACM, New York, NY, 1-3.
• FlexOS
• GEMSOS{{cite web |url=http://www.aesec.com/eval/NCSC-FER-94-008.pdf |title= Final evaluation report |date=June 28, 1995 |website= www.aesec.com|access-date=2020-09-14}} – TCSEC A1-class, secure kernel for BLACKER VPN & GTNP
• GEOS
• Genera 7.0
• HP-UX
• SunOS 3.0
• TR-DOS
• TRIX
• Version 9 Unix
• 1987
• Arthur (much improved version came in 1989 under the name RISC OS)
• BS2000 V9.0
• IRIX (3.0 is first SGI version)
• MDOS
• MINIX 1.0
• OS/2 (1.0)
• PC-MOS/386
• Topaz{{cite tech report |last1=Thacker |first1=Charles P. |last2=Stewart |first2=Lawrence C. |date=1987 |title=Firefly: A Multiprocessor Workstation |institution=Digital Equipment Corporation — Systems Research Center |number= |url=http://bitsavers.trailing-edge.com/pdf/dec/tech_reports/SRC-RR-23.pdf }} – semi-distributed OS for DEC Firefly workstation written in Modula-2+ and garbage collected
• Windows 2.0
• 1988
• A/UX (Apple Computer)
• AOS/VS II (Data General)
• CP/M rebranded as DR-DOS
• Flex machine – tagged, capability machine with OS and other software written in ALGOL 68RS
• GS/OS
• HeliOS 1.0
• KeyKOS – capability-based microkernel for IBM mainframes with automated persistence of app data
• LynxOS
• Mac OS (System 6)
• MVS/System Product V3 (MVS/Enterprise Systems Architecture, MVS/ESA)
• OS/2 (1.1)
• OS/400
• RISC iX
• SpartaDOS X
• SunOS 4.0
• TOPS-10 7.04 (Last stable release, July 1988)
• Virtual Machine/Extended Architecture System Product (VM/XA SP)
• VAX VMM{{Cite journal

| journal = IEEE Journal of Software Engineering

| title = A Retrospective on the VAX VMM Security Kernel

| volume = 17

| issue = 11

| pages = 1147–1165

| date = November 1991

| author1 = Paul A. Karger

| author2 = Mary Ellen Zurko

| author3 = Douglass W. Bonin

| author4 = Andrew H. Mason

| author5 = Clifford E. Kahn

| doi = 10.1109/32.106971

| url = http://www.cs.dartmouth.edu/~ccpalmer/classes/cs55/Content/resources/vax_vmm.pdf

| access-date = May 2, 2014

| archive-url = https://web.archive.org/web/20151112124406/http://www.cs.dartmouth.edu/~ccpalmer/classes/cs55/Content/Resources/vax_vmm.pdf

| archive-date = November 12, 2015

| url-status = dead

| df = mdy-all

}}

– TCSEC A1-class, VMM for VAX computers (limited use before cancellation)

• 1989
• Army Secure Operating System (ASOS){{cite report

| title = Quarterly Status Report - Report #1

| id = AD-A206 308

| date = 15 March 1989

| work = Advance Computing Systems: An Advanced Reasoning-Based Paradigm for Ada Trusted Systems and its Application to MACH

| url = https://apps.dtic.mil/dtic/tr/fulltext/u2/a206308.pdf

| archive-url = https://web.archive.org/web/20210602213045/https://apps.dtic.mil/dtic/tr/fulltext/u2/a206308.pdf

| url-status = live

| archive-date = June 2, 2021

| via = Defense Technical Information Center (DTIC)

| publisher = TRW - Federal Systems Group - Systems Division

}} – TCSEC A1-class secure, real-time OS for Ada applications

• EPOC (EPOC16)
• 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)

• 1990
• AIX 3.0
• AmigaOS 2.0
• BeOS (v1)
• DOS/V
• Genera 8.0
• iS-DOS
• LOCK{{cite web|url=http://www.cyberdefenseagency.com/publications/LOCK-An_Historical_Perspective.pdf |title=LOCK-An Historical Perspective |publisher=Cyberdefenseagency.com |access-date=2019-01-28}} – TCSEC A1-class secure system with kernel and hardware support for type enforcement
• MVS/ESA SP Version 4
• Novell NetWare 3
• OS/2 1.3
• OSF/1
• RTEMS
• PC/GEOS
• Windows 3.0
• Virtual Machine/Enterprise Systems Architecture (VM/XA ESA)
• VSE/Enterprise Systems Architecture (VSE/ESA) Version 1{{cite web

| title = IBM VSE/ENTERPRISE SYSTEMS ARCHITECTURE VERSION 1 RELEASE 1

| id = LTR 290-785

| date = December 18, 1990

| url = https://www.ibm.com/common/ssi/ShowDoc.wss?docURL=/common/ssi/rep_ca/5/897/ENUS290-785/index.html

| work = Announcement Letters

| publisher = IBM

| access-date = March 26, 2023

}}

• 1991
• Amoeba – microkernel-based, POSIX-compliant, distributed OS
• GNO/ME
• Linux 0.01-0.1
• Mac OS (System 7)
• MINIX 1.5
• PenPoint OS
• RISC OS 3{{citation

|url = http://www.wrocc.org.uk/riscos/history.shtml

|title = A Brief History of RISC OS

|work = Wakefield RISC OS Computer Club

|access-date = 2011-11-19

}}

• SUNMOS
• Trusted Xenix{{cite web|url=http://webapp1.dlib.indiana.edu/virtual_disk_library/index.cgi/1347159/FID1806/epl/entries/csc-epl-92-001.html|title=EPL Entry CSC-EPL-92/001|access-date=March 15, 2015}} – rewritten & security enhanced Xenix evaluated at TCSEC B2-class
• 1992
• 386BSD 0.1
• Amiga Unix 2.01 (Latest stable release)
• AmigaOS 3.0
• BSD/386, by BSDi and later known as BSD/OS.
• LGX
• 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)
• RSTS/E 10.1 (Last stable release, September 1992)
• SLS
• Solaris 2.0 (Successor to SunOS 4.x; based on SVR4 instead of BSD)
• Windows 3.1
• 1993
• IBM 4690 Operating System
• FreeBSD
• NetBSD
• Novell NetWare 4
• Newton OS
• Nucleus RTOS
• Open Genera 1.0
• OS 2200 (Unisys)
• OS/2 2.1
• PTS-DOS
• 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
• NetBSD 1.0 (First multi-platform release, October 1994)
• OS/2 Warp 3.0
• Red Hat
• RISC OS 3.5
• SPIN – extensible OS written in Modula-3
• 1995
• Digital UNIX (aka Tru64 UNIX)
• OpenBSD
• OS/390
• Plan 9 Second Edition (Commercial second release version was made available to the general public.)
• SMSQ/E
• Ultrix 4.5 (Last major release)
• Windows 95
• 1996
• AIX 4.2
• Debian 1.1
• JN{{cite web |url=http://embedded.soe.ucsc.edu/pubs/tr96-29/html/tr96-29.html |title=JN: An Operating System for an Embedded Java Network Computer UCSC-CRL-96-29 |access-date=2014-04-25 |url-status=dead |archive-url=https://web.archive.org/web/20120824010637/http://embedded.soe.ucsc.edu/pubs/tr96-29/html/tr96-29.html |archive-date=August 24, 2012 |df=mdy-all }} – microkernel OS for embedded, Java apps
• Mac OS 7.6 (First officially-named Mac OS)
• OS/2 Warp 4.0
• Palm OS
• RISC OS 3.6
• Windows NT 4.0
• Windows CE 1.0
• 1997
• AIX 4.3
• DR-WebSpyder 1.0
• EPOC (EPOC32)
• Inferno
• Mac OS 8
• MINIX 2.0
• Nemesisvarious 1997 publications listed on [http://www.cl.cam.ac.uk/research/srg/netos/old-projects/nemesis/documentation.html the Nemesis website], retrieved 2013-08-13
• RISC OS 3.7
• SkyOS
• Windows CE 2.0
• 1998
• DR-WebSpyder 2.0
• Junos
• Novell NetWare 5
• RT-11 5.7 (Last stable release, October 1998)
• Solaris 7 (first 64-bit Solaris release – names from this point drop "2.", otherwise would've been Solaris 2.7)
• Windows 98
• 1999
• Amiga OS 3.5 (unofficial)
• AROS (Boot for the first time in Stand Alone version)
• Inferno Second Edition (Last distribution (Release 2.3, {{circa|July 1999}}) from Lucent's Inferno Business Unit){{citation

|url = http://www.vitanuova.com/inferno/downloads.html

|title = Inferno Downloads

|work = Vita Nuova Holdings

|access-date = 2011-11-19

}}

• Mac OS 9
• OS/2 Warp 4.5
• RISC OS 4
• Windows 98 (2nd edition)

{{Further|Timeline of free and open-source software}}

• 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)

{{Reflist}}

• [http://www.levenez.com/unix/ UNIX History] – a timeline of UNIX 1969 and its descendants at present
• [http://bravotech.us/info/msos-timeline.htm Concise Microsoft O.S. Timeline] – a color-coded concise timeline for various Microsoft operating systems (1981–present)
• [http://www.bitsavers.org/ Bitsavers] – an effort to capture, salvage, and archive historical computer software and manuals from minicomputers and mainframes of the 1950s, 1960s, 1970s, and 1980s
• [http://www.cs.uiowa.edu/~jones/opsys/notes/03.shtml A brief history of operating systems]
• [http://www.guidebookgallery.org/timelines/windows Microsoft operating system time-line]

{{Operating system}}

{{Timelines of computing}}

*Timeline of operating systems

Operating systems

Real-time operating systems

Embedded operating systems