A piece of history went to GitHub: Microsoft made available in the repository the full source code of versions 1.25 and 2.0 of the good old MS-DOS. Launched between 1981 and 1983, the two systems were the foundation of the IBM PC and the IBM XT, two pioneering machines and chiefly responsible for computers as we know it today.
The MS-DOS v1.25 code is relatively simple. There are only seven files in Assembly that, for the current Explorer accounts, total less than 300 Kb. The system was launched in March 1982, almost a year after the release of its version 1.0.
MS-DOS v2.0 arrived in 1983 and marked almost a revolution on the young platform - just see the size of the source code, composed of over 100 files in Assembly. As the report in The Register points out, the OS was a milestone for Microsoft to support IBM XT 180 and 360 Kb floppies and their clones as well as 32 MB hard drives.
The idea of Microsoft releasing the source code of both in Github is to facilitate access to the material and even encourage the creation of forks. The system had already been made available in 2014 in the Computer History Museum under the same license, which allowed the development of derivatives. The big problem is that the site is not exactly a reference point for programmers like the repository - which happened to be purchased by Microsoft this year.