OS/2 was initially a joint effort between Microsoft and IBM. After version 1.3 was released, the two split up, and IBM went on to rewrite OS/2 and create version 2.0, while Microsoft released Windows 3.1 and used what they had done to create Windows NT.

OS/2 Warp 4, released in 1996, is the final version of OS/2. Although IBM indicated that OS/2 support would be stopped shortly after release, they went on to release version 4.52, and IBM's own support for the operating system didn't end until December 31, 2006. OS/2 is still supported to this day, although it is now being sold by Serenity Systems under the eComStation name.

This is the splash screen.

On first boot you are greeted with a whole mess of things on the desktop.

The first thing is this little welcome program which allows you to run registration (even though it runs itself anyways), or view a tutorial.
The program itself starts up with a whirlwind animation, presumably to conicide with the name "warp".

The other thing Warp 4 does is thrust a registration wizard in your face. It will do this every single time you log in (although presumably there is some way to stop it from doing that), however unlike Windows XP and later, which bundle the Windows Geniune Disadvantage technology, this is by no means required.

The default desktop looks different from Warp 3. The "Launchpad" has been removed in favor of a static-positioned "WarpBar", which contains a central menu similar to the Windows 95 taskbar of the time.

Also on the WarpBar, in order:

• An application switcher
• Lockup: Allows you to lock the screen and require a password, so you can leave and not worry about anyone snooping on your machine.
• Find objects
• Shutdown
• A disk space monitor. When clicked, you can also display a battery meter and a CPU monitor.
• A button that opens up a list of trays you have created for storing shortcuts
• A drive/file list
• A printer list
• A volume control (opens an applet when clicked)
• A list of system control panel applets
• A list of command prompts/Win-OS/2 stuff
• The assistance center
• Date and time

The desktop contains icons for:

• OS/2 System: Lists all the items, configuration tools, and other things pertaining to your system.
• Assistance Center: Contains programs and links that help you use OS/2.
• Connections: Contains a list of all the drives, network connections and printers attached to the system.
• Programs: Contains icons leading to
• WebExplorer (opens a window containing both the Modem-based version and the LAN-based version)
• A link to a now-presumably-dead Netscape download
• Shredder, which allows you to destroy documents, albeit permanently.

Like previous versions of OS/2, there are a few quirks not found in Windows, such as the right mouse button being used to drag things around as opposed to the traditional left mouse button. Of course this can be changed very easily; OS/2 is much more customizable than Windows is, even till today.