X86 DOS Comparison

Brief DOS History

• 1973: Gary Kildall writes a simple operating system which he calls CP/M
• April 1980: Tim Paterson begins writing an operating system for use with Seattle Computer Products' 8086-based computer, due to delays by Digital Research in releasing their CP/M-86 operating system.
• August 1980: QDOS 0.10 (Quick and Dirty Operating System) is shipped by Seattle Computer Products.
• October 1980: Microsoft pays less than US$100,000 for the right to sell SCP's DOS to an unnamed client (IBM).
• December 1980: Microsoft buys non-exclusive rights to market 86-DOS.
• December 1980: Digital Research releases CP/M-86
• July 1981: Microsoft buys all rights to QDOS from Seattle Computer Products, and the name MS-DOS is adopted.
• August 1981: IBM announces the IBM 5150 PC Personal Computer, featuring a 4.77-MHz Intel 8088 CPU, 64KB RAM, 40KB ROM, one 5.25-inch floppy drive, and PC-DOS 1.0
• May 1982: Microsoft releases MS-DOS 1.1
• March 1983: MS-DOS 2.0 for PCs is announced.
• October 1983: IBM introduces PC-DOS 2.1
• March 1984: Microsoft releases MS-DOS 2.1
• August 1984: Microsoft releases MS-DOS 3.0. It adds support for 1.2 MB floppy disks, and bigger than 10 MB hard disks.
• November 1984: Microsoft releases MS-DOS 3.1
• January 1986: Microsoft releases MS-DOS 3.2. It adds support for 3.5-inch 720 KB floppy disk drives.
• August 1987: Microsoft ships MS-DOS 3.3.
• November 1987: Compaq ships Compaq MS-DOS 3.31 with support for hard disk partitions over 32 MB.
• January 1988: Digital Research transforms CP/M into DR-DOS.
• May 1988: Digital research releases DR-DOS 3.31, supporting hard disk partitions up to 512 MB.
• June 1988: Microsoft releases MS-DOS 4.0, including a graphical/mouse interface.
• July 1988: IBM ships PC-DOS 4.0. It adds a shell menu interface and support for hard disk partitions over 32 MB.
• 1989: ROM-DOS introduced by Datalight.
• May 1990: Digital Research releases DR-DOS 5.0.
• June 1991: Microsoft releases MS-DOS 5.0. Edlin is replaced with a full-screen editor. It adds undelete and unformat utilities, and task swapping. GW-BASIC is replaced with Qbasic.
• September 1991: Digital Research releases DR-DOS 6.0 with Superstore disk compression.
• March 1993: Microsoft introduces MS-DOS 6.0, including DoubleSpace disk compression.
• April 1993: Novell acquires Digital Research
• November 1993: Microsoft releases MS-DOS 6.2.
• December 1993: Novell releases Novell DOS 7.0.
• February 1994: Microsoft releases MS-DOS 6.21, removing DoubleSpace disk compression.
• April 1994: IBM releases PC-DOS 6.3.
• June 1994: Microsoft releases MS-DOS 6.22, bringing back disk compression under the name DriveSpace.
• June 1994: PD-DOS, the open-source project later known as FreeDOS, is announced.
• April 1995: IBM releases PC-DOS 7, with integrated data compression from Stac Electronics (Stacker).
• July 1995: PTS-DOS 7.0 is released.
• January 1997: Novell sells Novell DOS to Caldera Systems, who release it as open-source OpenDOS 7.01
• December 1997: Caldera releases OpenDOS 7.02 as closed-source software.
• April 1998: IBM releases PC-DOS 7.1 (aka PC-DOS 2000), which is Y2K compliant.
• June 1999: Caldera Systems sells OpenDOS to Lineo, who release it as DR-DOS 7.03.
• September 1999: PTS-DOS 2000 is released.
• December 1999: Lineo releases an OEM-only version of DR-DOS 7.04.
• January 2000: Lineo releases DR-DOS 7.05 beta but soon drops development on it.
• July 2002: Udo Kuhnt starts the DR-DOS/OpenDOS Enhancement Project, based on the opensource OpenDos 7.01.
• October 2002: Lineo sells DR-DOS to DeviceLogics.
• March 2004: DeviceLogics releases DR-DOS 8.0
• November 2004: FreeDOS beta 0.9 is released.

Basic general information about the DOS packages: creator/company, file systems supported, etc.

Notes

Note 1: Current understanding has it that if one has a license to run a Windows version, one can also legally install any MS-DOS version up to the level of that Windows' version. Note 2: MS-DOS 8.0 has most of the functionality of previous versions, but there are significant losses of usability, like: the loss of FORMAT /S command; loss of SYS A: (or SYS B:) command for floppies; inability to boot to a command prompt without substitution/modification of IO.SYS and COMMAND.COM. Note 3: The limit of 124.55GB for FAT32 partition size is a limitation of Microsoft's SCANDISK utility. Microsoft's KB article 184006. Other DOS versions supporting FAT32 may allow a larger partition size closer to the theoretical ~2TB maximum suggested by FAT32's specifications.

See also

• CP/M
• DR-DOS
• MS-DOS
• PC-DOS