MS-DOS is an acronym for Microsoft Disk Operating System.

Version 2.00 was first version of MS-DOS 2 and was released in March of 1983, it added support for subdirectories, hard drives with up to 10 MB capacity and new commands. The successor to this was 2.01 which was released in November of 1983, it added international support and had other special releases for specific computers (MS-DOS 2.01a for the Wang Professional Computer, MS-DOS 2.05 for the DEC Rainbow, MS-DOS 2.10 for the Eagle Computers). The next release was version 2.02 as an OEM version for COMPAQ Plus computers only (this version has not yet been leaked). The next release was version 2.11 which was released in October 1983 by a number of OEM’s and had other special releases for specific computers (MS-DOS 2.11D for the Ericsson, MS-DOS 2.11R is a version of MS-DOS 2.11 burned into a ROM chip on the Tandy 1000 computer models, MS-DOS/Z-DOS 2.13 for the Zenith Z-100, MS-DOS/Z-DOS 2.18 for the Zenith Z-100 OEM of MS-DOS 2.11, MS-DOS 2.12 for COMPAQ, MS-DOS/Z-DOS 2.21 as an upgrade for MS-DOS 2.13). The final MS-DOS 2.x version is 2.25 which remains as a mystery to all experts although it’s speculated to have been released in October 1985. The next edition of MS-DOS was 3.x which was released in August of 1984.