OS/2

IBM OS/2
Logo
Screenshot
DeveloperIBM, Microsoft (1.x)
Source modelClosed source
Initial releaseOS/2 1.0
(December 1987)
Latest releaseOS/2 Warp 4.52
(December 2001)
Supported platformsx86, PowerPC, NEC PC-9801
Kernel typeHybrid
User interfaceWorkplace Shell
LicenseProprietary

OS/2 (Operating System/2) is an operating system originally developed jointly by Microsoft and IBM, in development was codenamed "CP/DOS". Between the release of Windows 3.0 and OS/2 1.3, Microsoft stopped all cooperation with IBM, due to a feud between the companies' significantly different cultures and visions. IBM later on handled the development of the operating system by itself.

OS/2 has features like a virtual DOS machine, the WIN-OS/2 subsystem (Windows 3.0/3.1x inside OS/2), Presentation Manager, and more.

Microsoft later used the OS/2 code to develop Windows NT 3.1. The code was later used by Serenity Systems to develop eComStation in 2001, which in turn was used by Arca Noae LLC to develop ArcaOS in 2017.

NEC sold a port of the Japanese localized version for their PC-9801 series of computers. This port features NEC copyrights as well as IBM and/or Microsoft copyrights along with NEC's own modified version of DOS.

Timeline[edit | edit source]

OS/2 Classic versions

Name Version Codename Release date Notes
OS/2 1.0 1.0 CP/DOS 1987-12 First version of OS/2 released without GUI
OS/2 1.1 1.1 Trimaran 1988-10 First version with the Presentation Manager
OS/2 1.2 1.2 Sloop 1989-10 Updated UI to resemble Windows 3.0
OS/2 1.3 1.3 Cutter 1990-12 Last version to be sold through Microsoft
OS/2 2.0 2.0 Cruiser 1992-04 First version to include WIN-OS/2 with Windows 3.0; replaced Presentation Manager with Workplace Shell
OS/2 2.00.1 2.00.1 Riker 1992-10
OS/2 2.1 2.1 Borg, Yawl 1993-05 Updated Windows version of WIN-OS/2 to 3.1
OS/2 2.11 2.11 1994-02
Legend:
Old version
Older version, still supported
Current stable version
Latest preview version
Future release

OS/2 Warp versions

Name Version Codename Release date Notes
OS/2 Warp 3 3.0 Warp 1994-10 Introduces Launchpad; only version to support PPC-based systems
OS/2 Warp 4 4.0 Merlin 1996-09-25 Replaced Launchpad as default shell with WarpCenter
OS/2 Warp Server for e-Business 4.5 Aurora 1999-04
OS/2 Warp 4.51 4.51 MCP/ACP 2000-11
OS/2 Warp 4.52 4.52 MCP2/ACP2 2001-12 Last version of OS/2
Legend:
Old version
Older version, still supported
Current stable version
Latest preview version
Future release