Name	Creator	First Release	Predecessor	Latest Stable Version	Latest Release Date	Cost Availability	Preferred License	Target System
AIX	IBM	1986-?-?	System V R3	?	2007-11-?	Bundled with hardware	Proprietary	Server, NetApp, Workstation
AmigaOS 4	Amiga, Inc. / Hyperion Entertainment	39937	AmigaOS Classic	4.1	39707	Standalone package	Proprietary	Workstation, Home Desktop
AmigaOS Classic	Commodore International, Haage & Partner	31251	TRIPOS	3.9	?	Bundled with hardware	Proprietary	Workstation, Home Desktop
FreeBSD	The FreeBSD Project	1993-12-?	386BSD	7.2	39937	Free	BSD	Server, Workstation, NetApp, Embedded
Haiku	Haiku Inc.	-	BeOS R5		(Nightly builds)	Free	MIT License	Home Desktop
HP-UX	Hewlett-Packard	1983-?-?	Unix	11.31 11i v3	39128	$400	Proprietary	Server, Workstation
Inferno	Bell Labs	1997-?-?	Plan 9	Fourth Edition	2007-02-?	Free	MIT/GNU GPL/GNU LGPL/LPL	NetApp, Server, Embedded
Linux	Linus Torvalds, et al.	33841	Unix4, Minix5	Linux kernel 2.6.30; GNU C Library 2.7	2008-12-14; 2007-10-23	See Comparison of Linux distributions	GNU GPL, GNU LGPL and other licenses	
Mac OS Classic	Apple Inc.	30705	None2 7	9.2.2	37388	Bundled with 68K and PowerPC Macs;		
Mac OS X	Apple Inc.	36974	NeXTStep / OPENSTEP / Rhapsody, Mac OS, UNIX	10.5.8 Leopard	40030	Bundled with hardware; upgrades sold separately:		
Microsoft Windows (NT family)	Microsoft	31371	MS-DOS, OS/2, Windows 3.x	Windows 7 (NT 6.1.7600)	2006 November - 2007 January 8	Home Basic (Retail) $99.95, Home Premium (Retail) $119.95, Business (Retail) $299.95, Ultimate (Retail) $300.95[1]	Proprietary	Workstation, Home Desktop, media center, Tablet PC, embedded
Minix3	Andrew S. Tanenbaum	2005-10-?	Minix2	3.1.2a	38866	Free	BSD	Workstation
NetBSD	The NetBSD Project	1993-05-?	386BSD	?	39932	Free	BSD	NetApp, Server, Workstation, Embedded
NetWare	Novell	1985	S-Net	6.5 SP7	2007-10-?	$184 (single-user)	Proprietary	Server
OpenBSD	The OpenBSD Project	1995-10-?	NetBSD 1.0	?	39934	Free	BSD	Server, NetApp, Workstation, Embedded
OpenSolaris	Sun	2008.05	Solaris	2009.06	39965	Free	CDDL	Desktop, Workstation, Server
OpenVMS	DEC (now HP)	28423	RSX-11M	8.3-1H1	2007-10-?	Free for non-commercial use	Proprietary	Server, Workstation
OS/2	IBM and Microsoft	1987-12-?	MS-DOS, Windows 3.x	4.52	2001-12-?	$300	Proprietary	Home Desktop, Server
PC-BSD	PC-BSD Software	2006-?-?	FreeBSD6	7.1	39818	Free	BSD	Desktop, Workstation, Server
Plan 9	Bell Labs	1993-?-?	Unix	Fourth Edition	(Daily snapshots)	Free	LPL	Workstation, Server, Embedded, HPC
QNX	QNX Software Systems	1982-?-?	Unix	6.4.1	39961	?	Proprietary	Workstation, Server, Embedded
ReactOS	ReactOS development team	1996-?-?	Windows NT	0.3.10	39999	Free	GNU GPL, GNU LGPL	Workstation, Home Desktop
RISC OS	Acorn Computers, RISC OS Limited, Castle Technology Ltd	1989-04-?	ARTHUR, also the BBC Master OS	RISC OS 6.10 Select4i4 and RISC OS 5.13	39596	Bundled with hardware, then sold separately at $127 (70)	Proprietary	educational desktop, home computer
Solaris	Sun	1992-07-?	SunOS	10.55555556	39553	Free	CDDL	Server, Workstation
STOP 6 / XTS-400	BAE Systems	2003-?-?	STOP 5 / XTS-300	6.4.U1	2007-06-?	Unknown; supplied to customers on-demand by BAE Systems	Proprietary	Server, Workstation, cross-domain solution, network guard
Windows Server (NT family)	Microsoft	34177	MS-DOS, OS/2, Windows 3.x	Windows Server 2008 (NT 6.0)	39505	$469 Web Server; other editions dependent on number of CALs purchased	Proprietary	Server, NetApp, Embedded, HPC
z/OS	IBM	-	OS/390	1.9	2007	Monthly License Charge (about $130 and up)	Proprietary	IBM mainframe
ZETA	yellowTAB	2005-06-?	BeOS R5	1.2	38834	Professional $110, Student $80	Proprietary	Home Desktop, Media Workstation
