IBM PC-DOS was an IBM branded version of MS-DOS licensed from Microsoft for use on the IBM PC system. Versions of PC-DOS paralleled that of MS-DOS up until version 6.1, where PC-DOS was independently maintained by IBM up until 7.1, the last version. Although not the only OS available for the IBM PC when it came out, it quickly became popular due to its low cost in comparison to the others. Its direct competitors on the PC at the time were CP/M-86 and UCSD p-System. The major differences between PC-DOS and MS-DOS were only in terms of driver support and built in programs until version 6.1 where development diverged.
For Microsoft and other OEM DOS releases, please see the MS-DOS product page.
The first version of PC-DOS was released in August 1981 with the IBM PC. The last version released by IBM was PC-DOS 7.1, which had updates all the way up until 2003. This last version of DOS is still in use by some hardware developers usually embedded into recovery tools and BIOS flashers.
This OS does not have a GUI. It uses a command line interface, however PC-DOS 4 and later, like MS-DOS, also included the optional graphical DOSShell program. Like other DOSes, third party GUIs can be installed.
PC-DOS 3.x was introduced for IBM's 286 based AT computer. It adds support for IBM's 1.2mb floppy drive, hard disk partitions up to 32mb, and adds features for use with networking.
The Convertible release is the customized DOS startup disk included with the IBM PC Convertible (IBM 5140). The included programs will only run on the IBM PC Convertible.