cover image

OS/2 (Operating System/2) is a series of computer operating systems, initially created by Microsoft and IBM under the leadership of IBM software designer Ed Iacobucci.[2] As a result of a feud between the two companies over how to position OS/2 relative to Microsoft's new Windows 3.1 operating environment,[3] the two companies severed the relationship in 1992 and OS/2 development fell to IBM exclusively.[4] The name stands for "Operating System/2", because it was introduced as part of the same generation change release as IBM's "Personal System/2 (PS/2)" line of second-generation personal computers. The first version of OS/2 was released in December 1987 and newer versions were released until December 2001.

Quick facts: Developer, Written in, Working state, Source ...
OS/2 Warp 4 desktop. This version was released on 25 September 1996.[1]
Microsoft (1.0–1.3)
Written inC, C++ and assembly language
Working stateHistorical, now developed as ArcaOS
Source modelClosed source
Initial releaseDecember 1987; 35 years ago (1987-12)
Latest release4.52 / December 2001; 21 years ago (2001-12)
Marketing targetProfessionals, servers
Available inChinese, English, French, German, Italian, Japanese, Korean, Spanish, Slovenian, Portuguese, Russian
Platformsx86, PowerPC
Kernel typeHybrid kernel
Influenced byMS-DOS, IBM PC DOS
user interface
Workplace Shell Graphical user interface
Succeeded byFirst by eComStation, then ArcaOS
Official websiteOS/2 Warp (Archived)

OS/2 was intended as a protected-mode successor of PC DOS. Notably, basic system calls were modeled after MS-DOS calls; their names even started with "Dos" and it was possible to create "Family Mode" applications – text mode applications that could work on both systems.[5] Because of this heritage, OS/2 shares similarities with Unix, Xenix, and Windows NT.

IBM discontinued its support for OS/2 on 31 December 2006.[6] Since then, OS/2 has been developed, supported and sold by two different third-party vendors under license from IBM – first by Serenity Systems as eComStation since 2001,[7] and later by Arca Noae LLC as ArcaOS since 2017.[8][9][10]

Oops something went wrong: