An Internet user fond of old software and documents has discovered the oldest version of the predecessor of MS-DOS known to date. It is available for download and you can install it on your machine.
Today, your computer is most likely running Windows 11 or Windows 10. Obviously, this numbering indicates that there were other iterations of the operating system before that. And even before Windows 1.0 arrived, there was MS-DOS. A rudimentary program taking the form of a black screen on which you had to type lines of code to launch programs. For the record, the screenplay for the 2021 film Dune was written on it. But did you know there was something before MS-DOS? This dates back to the beginning of 1980.
At that time, Tim Paterson was a developer within the company Seattle Computer Products. He created QDOSacronym for Quick and Dirty Computer System. A not very commercial name which will quickly be replaced by 86-DOSaccording to the Intel 8086 processor. It is this version that Microsoft would eventually buy it in 1981 and rename it MS-DOS. Until now, the oldest version of 86-DOS known to date was the 0.34. The Internet user f15sim who found it while searching the site Internet Archive did better since he spotted the 0.1.
Oldest ancestor of MS-DOS discovered and made available for download
More precisely, it is 86-DOS version 0.1 C Serial #11, as can be seen in the photo below. As you can imagine: it contains very few programs. However, you can play chess while typing and access documents concerning this game. This version of the operating system dates from August 1980, shortly after the name change. It nevertheless resembles what MS-DOS will be a little later.
If you are curious, it is possible to download 86-DOS version 0.1 C and install it using theSIMH emulator. There is a link to detailed instructions. The process is not as complicated as you might imagine, and you can even access 86-DOS manuals to make the best use of the system.