Microsoft Release Disk Operating System Source Code To the Public


Early versions of MS-DOS and Word for Windows have been contributed to the Computer History Museum who will make the source code available to the public. Microsoft hopes that by making the source code available (distributed under a research license), future technologists will better understand the origins of personal computing. MS-DOS 1.1 and 2.0 were the product of Microsoft’s project to create an operating system for IBM PC’s. MS-DOS 1.1 is an entire operating system that fits inside 1.2 KB of memory.

“MS-DOS and Word for Windows built the foundation for Microsoft’s success in the technology industry,” said Roy Levin, distinguished engineer and managing director, Microsoft Research. “By contributing these source codes to the Computer History Museum archives, Microsoft is making these historic systems from the early era of personal computing available to the community for historical and technical scholarship.”

Microsoft paid Seattle Computer Company for its Q-OS which it later transformed into MS-DOS. Version 2.0 of Microsoft’s software introduced a filesystem which supported 10 MB of hard drive space. After MS-DOS 6 came Win 95 with support for VFAT, with the last general purpose version of DOS being 7.1.
Word for Windows was created by Charles Simonyi drawing from an original project called Multi-Tool Word. Its release in 1989 changed word processing and as described in the CHM blogpost, “It was a remarkable marketing and engineering achievement.”

The CHM has made several versions of historic source code available, namely: APPLE II DOS, IBM APL, Apple Macpaint and Quickdraw and Adobe Photoshop.