OS/2

OS/2 is a computer operating system, initially created by Microsoft and IBM, then later developed by IBM exclusively. 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. OS/2 is no longer marketed by IBM, and IBM standard support for OS/2 was discontinued on 31 December 2006.