Microsoft makes source code for MS-DOS and Word for Windows available to public

The following post is from Roy Levin, distinguished engineer and managing director, Microsoft Research Silicon Valley.

On Tuesday, we dusted off the source code for early versions of MS-DOS and Word for Windows. With the help of the Computer History Museum, we are making this code available to the public for the first time.

The museum has done an excellent job of curating some of the most significant historical software programs in computing history. As part of this ongoing project, the museum will make available two of the most widely used software programs of the 1980’s, MS DOS 1.1 and 2.0 and Microsoft Word for Windows 1.1a, to help future generations of technologists better understand the roots of personal computing.

In 1980, IBM approached Microsoft to work on a project code-named “Chess.” What followed was a significant milestone in the history of the personal computer. Microsoft, at the time, provided the BASIC language interpreter for IBM. However, they had other plans and asked Microsoft to create an operating system. Without their own on hand, Microsoft licensed an operating system from Seattle Computer Products which would become the foundation for PC-DOS and MS-DOS.

IBM and Microsoft developed a unique relationship that paved the way for advancements in the nascent personal computer industry, and subsequent advancements in personal computing.

Bill Gates was interviewed by David Bunnell just after the launch of the IBM PC in the early 1980s for PC Magazine’s inaugural issue, and provided the backstory: “For more than a year, 35 of Microsoft’s staff of 100 worked fulltime (and plenty of overtime) on the IBM project. Bulky packages containing computer gear and other goodies were air-expressed almost daily between the Boca Raton [IBM] laboratory and Seattle [Microsoft]. An electronic message system was established and there was almost always someone flying the arduous 4,000 mile commute.”

Following closely on the heels of MS DOS, Microsoft released the first DOS-based version of Microsoft Word in 1983, which was designed to be used with a mouse. However, it was the 1989 release of Word for Windows that became a blockbuster for the company and within four years it was generating over half the revenue of the worldwide word-processing market. Word for Windows was a remarkable engineering and marketing achievement, and we are happy to provide its source code to the museum.

It’s mind-boggling to think of the growth from those days when Microsoft had under 100 employees and a Microsoft product (MS-DOS) had less than 300KB (yes, kilobytes) of source code. From those roots we’ve grown in a few short decades to become a company that has sold more than 200 million licenses of Windows 8 and has over 1 billion people using Microsoft Office. Great things come from modest beginnings, and the great Microsoft devices and services of the future will probably start small, just as MS-DOS and Word for Windows did.

Thanks to the Computer History Museum, these important pieces of source code will be preserved and made available to the community for historical and technical scholarship.