Editing PTS-DOS (section)

== History and versions{{anchor|6.40|6.50|6.51|6.60|6.65|6.70|2000|7.00|32}} ==
PhysTechSoft was formed in 1991 in [[Moscow]], [[Russia]] by graduates and members of [[Moscow Institute of Physics and Technology|MIPT]], informally known as PhysTech. At the end of 1993, PhysTechSoft released the first commercially available PTS-DOS as PTS-DOS&nbsp;v6.4.<ref name="CW_1994_PTS"/><ref name="pts-about"/> The version numbering followed [[MS-DOS#Versions|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&nbsp;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,<ref name="pts-faq-en"/> as PTS-DOS was developed in close relationship with Russia's military and thus may be subject to [[military secret]]s law.

PhysTechSoft continued development on their own and released PTS-DOS v6.6 somewhere between<ref name="pts-faq-en"/> and presented PTS-DOS&nbsp;v6.65 at the [[CeBIT]] exhibition in 1997.<ref name="pts-about"/> The next version from PhysTechSoft, formally PTS/DOS Extended Version 6.70<ref name="pts-faq-de"/> was labeled PTS-DOS 2000 and is still being distributed as a last 16-bit PTS-DOS system, {{As of|2007|lc=on}}.

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.<ref name="pts-faq-de"/>

Later, PhysTechSoft continued developing PTS-DOS and finally released PTS-DOS 32, formally known as PTS-DOS v7.0,<ref name="pts-faq-de"/> which added support for the [[FAT32]] [[file system]].

PTS-DOS is certified by the [[Russian Ministry of Defense]].<ref name="pts-os"/>