PhysTechSoft was formed in 1991 in
Moscow,
Russia by graduates and members of
MIPT, informally known as PhysTech. At the end of 1993, PhysTechSoft released the first commercially available PTS-DOS as PTS-DOS v6.4. The version numbering followed
MS-DOS version numbers, as Microsoft released
MS-DOS 6.2 in November 1993. In 1995, some programmers left PhysTechSoft and founded
Paragon Technology Systems. They took source code with them and released their own version named PTS/DOS 6.51CD as well as S/DOS 1.0 ("Source DOS"), a stripped down open-source version. According to official PhysTechSoft announcements, these programmers violated both copyright laws and Russian military laws, as PTS-DOS was developed in close relationship with Russia's military and thus may be subject to
military secrets law. PhysTechSoft continued development on their own and released PTS-DOS v6.6 somewhere between and presented PTS-DOS v6.65 at the
CeBIT exhibition in 1997. The next version from PhysTechSoft, formally PTS/DOS Extended Version 6.70 was labeled PTS-DOS 2000 and is still being distributed as a last 16-bit PTS-DOS system, . Paragon continued their PTS-DOS line and released Paragon DOS Pro 2000 (also known and labeled in some places as PTS/DOS Pro 2000). According to Paragon, this was the last version and all development since then ceased. Moreover, this release contained bundled source code of older PTS-DOS v6.51. Later, PhysTechSoft continued developing PTS-DOS and finally released PTS-DOS 32, formally known as PTS-DOS v7.0, which added support for the
FAT32 file system. PTS-DOS is certified by the
Russian Ministry of Defense. == Commands ==