Fort Towson

Each version of the UNIX Time-Sharing System evolved from the version before, with version one evolving from the prototypal Unix. Not all variants and descendants are displayed.

Research Unix

"Ken's new system" (Unics → Unix) (1969)
UNIX Time-Sharing System v1 (1971)
UNIX Time-Sharing System v2 (1972)
UNIX Time-Sharing System v3 (1973)
UNIX Time-Sharing System v4 (1973)
UNIX Time-Sharing System v5 (1974)
- UNSW 01 (1978)
UNIX Time-Sharing System v6 (1975)
- 1BSD (1978)
- AUSAM (1978)
- IS/1 (1977)
- LSI-UNIX (1977)
- Mini-UNIX (1977)
- PWB/UNIX 1.0 (1977)
  - USG 1.0
    - CB UNIX 1
- Wollongong Unix (1977)

UNIX Time-Sharing System v7 (1979)
- 2BSD (1979)
- UNIX/32V (1979)
  - 3BSD (1979)
  - UNIX System III (1981)
- UNIX/V7M (1979)
UNIX Time-Sharing System v8 (1985)
UNIX Time-Sharing System v9 (1986)
UNIX Time-Sharing System v10 (1989)
- IX Multilevel-Secure UNIX System (1992)

The versions leading to v7 are also sometimes called Ancient UNIX. After the release of Version 10, the Unix research team at Bell Labs turned its focus to Plan 9 from Bell Labs, a distinct operating system that was first released to the public in 1993. All versions of BSD from its inception up to History of the Berkeley Software Distribution#4.3BSD|4.3BSD-Reno are based on Research Unix, with versions starting with History of the Berkeley Software Distribution#4.4BSD and descendants|4.4 BSD and History of the Berkeley Software Distribution#Net/2 and legal troubles|Net/2 instead becoming Unix-like.

Commercial AT&T UNIX Systems and descendants

Each of the systems in this list is evolved from the version before, with Unix System III evolving from both the UNIX Time-Sharing System v7 and the descendants of the UNIX Time-Sharing System v6.

UNIX System III (1981)
UNIX System IV (1982)
UNIX System V (1983)
- UNIX System V Release 2 (1984)
- UNIX System V Release 3.0 (1986)
- UNIX System V Release 3.2 (1987)
- UNIX System V Release 4 (1988)
- UNIX System V Release 4.2 (1992)
UnixWare 1.1 (1993)
- UnixWare 1.1.1 (1994)
UnixWare 2.0 (1995)
- UnixWare 2.1 (1996)
  - UnixWare 2.1.2 (1996)

UnixWare 7 (System V Release 5) (1998)
- UnixWare 7.0.1 (1998)
UnixWare 7.1 (1999)
- UnixWare 7.1.1 (1999)
- UnixWare NSC 7.1+IP (2000)
- UnixWare NSC 7.1+LKP (2000)
- UnixWare NSC 7.1DCFS (2000)
Open Unix 8 (UnixWare 7.1.2) (2001)
- Open Unix 8MP1 (2001)
- Open Unix 8MP2 (2001)
- Open Unix 8MP3 (2002)
- Open Unix 8MP4 (2002)
SCO UnixWare 7.1.3 (2002)
- SCO UnixWare 7.1.3 Update Pack 1 (2003)
- SCO UnixWare 7.1.4 (2004)

Forks and ports

Other Unix operating systems

Below are other certified Unix operating systems.^[2]

macOS

Heavily based on BSD, macOS is registered as certified Unix 03 brand on both versions (Intel and Apple silicon-based).

SCO OpenServer

Another operating system by SCO. Registered as Unix 93 “single and Multi-processor Industry Standard Intel architecture platform”.

z/OS

z/OS by IBM is listed as two different operating systems, z/OS and z/OS V2R1. Both are Unix 95.

Unix-like operating systems

Notes

^ Two of the distros are certified UNIX brands, Inspur K-UX and EulerOS.^[3]

References

^ "SunSoft introduces first shrink-wrapped distributed computing solution: Solaris". sun.com. 1991-09-04. Archived from the original on 2007-10-12. Retrieved 13 April 2024.
^ "The Register of UNIX® Certified Products". www.opengroup.org. Retrieved 2024-04-26.
^ https://www.theregister.com/2024/02/16/what_is_unix/

[4] Two of the distros are certified UNIX brands, Inspur K-UX and EulerOS.^[3]

[1] "SunSoft introduces first shrink-wrapped distributed computing solution: Solaris". sun.com. 1991-09-04. Archived from the original on 2007-10-12. Retrieved 13 April 2024.

[2] "The Register of UNIX® Certified Products". www.opengroup.org. Retrieved 2024-04-26.

[3] ttps://www.theregister.com/2024/02/16/what_is_unix/

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