Microsoft Releases First Version of OS/2

In December 1987, Microsoft and IBM officially released OS/2 version 1.0, the first version of the Operating System/2, as part of their joint effort to develop a successor to MS-DOS. The operating system was designed to take advantage of the protected mode capabilities of Intel 80286 processors and to introduce multitasking to IBM compatible personal computers. The release followed several years of collaboration between the two companies, which began in 1985 with the goal of building a more advanced platform for business computing. OS/2 1.0 launched as a 16 bit, text based operating system without a graphical user interface. It supported preemptive multitasking for character mode applications and provided improved memory management compared with MS-DOS, allowing programs to access protected mode memory beyond the conventional DOS limits. The system included a command line interface, basic system utilities, and support for running DOS applications in compatibility sessions. A graphical environment called Presentation Manager was not included in the initial release and arrived later with OS/2 1.1 in 1988. The December 1987 release reflected the early stage of next generation PC operating systems, with hardware requirements that were higher than typical DOS systems and limited third party software availability at launch. IBM positioned OS/2 for its Personal System/2 line, while Microsoft continued developing both OS/2 and Windows during the late 1980s. The collaboration continued until the early 1990s, when strategic differences led to the end of the partnership and separate operating system paths.