86-DOS was an operating system that Microsoft licensed (and later bought). create MS-DOS and Windows and will eventually completely dominate global consumer computing. The first known version of this development has been found and uploaded to the Internet Archive where it can be downloaded and used.

Every great ending has behind it small beginnings or a privileged mind like Bill Gates (a better businessman than programmer, the gossip says…) who saw the future of Tim Paterson’s original operating system, converted it to MS-DOS and managed to put it on the IBM PC launching in 1982. The rest is well known, but this is how the giant that dominates the Windows desktop today began to take shape.

The earliest version of 86-DOS

The story begins with the QDOS operating system created by Paterson in Seattle Computer Products (SCP). It was later renamed 86-DOS when the company developed its S-100 computer builds based on the Intel 8086 processor. In fact, This version was the one that Microsoft first licensed, then bought, and eventually renamed MS-DOS..

A few days ago an Internet Archive user discovered and uploaded a new version of 86-DOS to the Internet Archive, and it turns out that It is the oldest of those publicly available: 86-DOS version 0.1-C. Its ISO image is available for download and can be run using the SIMH emulator.

This version of 86-DOS is basic even by the standards of early 1980s DOS builds, containing only a few utilities, a text chess game, and its documentation. However, it remains essentially recognizable as DOS, which would take over the entire PC business before Windows and the breakthrough version.

Of course, commercial MS-DOS is still available, which you can use e.g. enjoy mythical games which were developed for the platform. Although the graphics and sound parts are incomparable with the current ones, they offer great fun today as they did yesterday, can be played with complete fluency on current machines and have qualities that many current titles lack: great playability.