A UNIX System Timeline

The following timeline summarizes the development of UNIX from its beginning to 2006. For an incredibly detailed timeline of releases of different UNIX variants, go to http://www.levenez.com/unix/.

Year	UNIX Variant or Standard	Comments
1969	UNICS (later called UNIX)	A new operating system invented by Ken Thompson and Dennis Ritchie for the PDP-7
1973	Fourth Edition	Written in C programming language; widely used inside Bell Laboratories
1975	Sixth Edition	First version widely available outside of Bell Labs; more than 600 machines ran it
1978	3BSD	Virtual memory
1979	Seventh Edition	Included the Bourne shell, UUCP, and C; the direct ancestor or modern UNIX
1980	Xenix	Introduced by Microsoft
1980	4BSD	Introduced by UC Berkeley
1982	System III	First public release outside of Bell Labs
1983	System V Release 1	First supported release
1983	4.1BSD	UC Berkeley release with performance enhancements
1984	4.2BSD	UC Berkeley release with many networking capabilities
1984	System V Release 2	Protection and locking of files, enhanced system administration, and job control features added
1986	HP-UX	First version of HP-UX released for HP Precision Architecture
1986	AIX Version 1	First version of IBM’s proprietary version of UNIX, based on SVR3
1987	System V Release 3	STREAMS, RFS, TLI added
1987	4.3BSD	Minor enhancements to 4.2BSD
1988	POSIX	POSIX.1 published
1989	System V Release 4	Unified System V, BSD, and Xenix
1990	XPG3	X/Open specification set
1990	OSF/1	Open Software Foundation release designed to compete with SVR4
1991	386BSD	Based on BSD for Intel 80386
1991	Linux 0.01	Linus Torvalds started development of Linux
1992	SVR4.2	USL-developed version of SVR4 for the desktop
1992	HP-UX 9.0	Supported workstations, including a GUI
1993	Solaris 2.3	POSIX compliant
1993	4.4BSD	Final Berkeley release
1993	FreeBSD 1.0	Initial release based on 4.3BSD and 386BSD
1993	SVR4.2MP	Last version of UNIX developed by USL
1994	Linux 1.0	First version of Linux not considered a “beta”
1994	NetBSD 1.0	First multiplatform release
1994	Solaris 2.4	Motif supported
1994	AIX4	Introduced CDE support
1994	FreeBSD 2.0	Based on 4.4BSD-Lite to allow free distribution
1995	UNIX 95	X/Open mark for systems registered under the Single UNIX Specification
1995	Solaris 2.5	CDE supported
1995	HP-UX 10.0	Conformed to the Single UNIX Specification and the Common Desktop Environment (CDE)
1996	Linux 2.0	Performance improvements and networking software added
1996	OpenBSD 1.2	Initial release with strong support of security
1997	Solaris 2.6	UNIX 95 compliant, JAVA supported
1997	Single UNIX Specification, Version 2	Open Group specification set
1997	System V Release 5	Enhanced SV kernel, including 64-bit support, increased reliability, and performance enhancements
1997	UnixWare 7	SCO UNIX based on SVR5 kernel
1997	HP-UX 11.0	64-bit operating system
1997	AIX 4.3	Support for 64-bit architectures, registered with UNIX 98 mark
1998	UNIX 98	Open Group mark for systems registered under the Single UNIX Specification, Version 2
1998	FreeBSD 3.0	Kernel changes and security fixes
1998	Solaris 7	Support for 64-bit applications, free for noncommercial users
1999	Linux 2.2	Device drivers added
1999	Darwin	Apple developed UNIX-like OS, basis for Mac OS X
2000	Solaris 8	Performance and application support enhancements
2000	HP-UX 11i	Introduces operating environments
2000	FreeBSD 4.0	Networking and security enhancements
2001	Linux 2.4	Enhanced device support, scalability enhancements
2001	AIX 5L	Introduced affinity for Linux
2001	Mac OS X 10.0 “Cheetah”	First Mac OS release based on Darwin. Incomplete and slow, but with basic OS features, device support, and software development environment
2001	Mac OS X 10.1 “Puma”	More complete than Cheetah, with performance enhancements and support for additional device drivers
2002	Solaris 9	Manageability, security, and performance enhancements
2002	Mac OS X 10.2 “Jaguar”	First solid release of Mac OS X
2003	Linux 2.6	Scalability for operation on embedded systems to large servers, human interface, networking, and security enhancements
2003	Mac OS X 10.3 “Panther”	Performance enhancements, an extensive update to the user interface, and greater interoperability with MS Windows
2003	Single UNIX Specification, Version 3	Developed by the Austin Group
2003	FreeBSD 5.0	Improved SMP support, TrustedBSD security features
2004	Solaris 10	Advanced security, performance, and availability enhancements
2004	NetBSD 2.0	Support for SMP
2005	OpenServer 6	Improved SMP support and support for extremely large files
2005	Mac X 10.4 “Tiger”	New features include Spotlight, a fast content and metadata-based file search tool, and support for 64-bit platforms and Intel x86 platforms
2005	Net BSD 3.0	Suppose Xen Virtual Machine Monitor