1973 Gary Kildall writes a simple operating system
in his PL/M language. He calls it CP/M (Control Program/Monitor).
(Control Program for Microcomputer) 1979 February
Apple Computer releases DOS 3.2. July
Apple Computer releases DOS 3.2.1 1980 April
Tim Patterson begins writing an operating system for use with Seattle
Computer Products' 8086-based computer.
Seattle Computer Products
decides to make their own disk operating system (DOS), due to delays by Digital
Research in releasing a CP/M-86 operating system. August
QDOS 0.10 (Quick and Dirty Operating System) is shipped by Seattle Computer
Products. Even though it had been created in only two man-months, the
DOS worked surprisingly well. A week later, the EDLIN line editor was
created. EDLIN was supposed to last only six months, before being replaced. September
Tim Patterson shows Microsoft his 86-DOS, written for the 8086 chip. October
Microsoft's Paul Allen contacts Seattle Computer Products' Tim Patterson, asking
for the rights to sell SCP's DOS to an unnamed client (IBM). Microsoft
pays less than US$100,000 for the right. December
Seattle Computer Products renames QDOS to 86-DOS, releasing it as version 0.3.
Microsoft then bought non-exclusive rights to market 86-DOS.
--- 1981 February
MS-DOS runs for the first time on IBM's prototype microcomputer. July
Microsoft buys all rights to DOS from Seattle Computer Products, and the name
MS-DOS is adopted. August
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 (Microsoft's
MS-DOS), for US$3000.
--- 1982 May
Microsoft releases MS-DOS 1.1 to IBM, for the IBM PC. It supports 320KB
double-sided floppy disk drives. Microsoft also releases MS-DOS 1.25, similar
to 1.1 but for IBM-compatible computers.
--- 1983 March
MS-DOS 2.0 for PCs is announced. It was written from scratch, supporting 10
MB hard drives, a tree-structured file system, and 360 KB floppy disks. October
IBM introduces PC-DOS 2.1 with the IBM PCjr.
--- 1984 March
Microsoft releases MS-DOS 2.1 for the IBM PCjr.
Microsoft releases MS-DOS 2.11. It includes enhancements to better allow
conversion into different languages and date formats. August
Microsoft releases MS-DOS 3.0 for PCs. It adds support for 1.2 MB floppy disks,
and bigger (than 10 MB) hard disks. November
Microsoft releases MS-DOS 3.1. It adds support for Microsoft networks.
--- 1986 January
Microsoft releases MS-DOS 3.2. It adds support for 3.5-inch 720 KB floppy disk
Microsoft releases MS-DOS 3.25.
--- 1987 April
IBM announces DOS 3.3 for PCs, for US$120. August
Microsoft ships MS-DOS 3.3. November
Compaq ships MS-DOS 3.31 with support for over 32mb drives.
Digital Research transforms CP/M into DR DOS. June
Microsoft releases MS-DOS 4.0, including a graphical/mouse
IBM ships DOS 4.0. It adds a shell menu interface and support for hard disk
partitions over 32 MB. November
Microsoft releases MS-DOS 4.01.
--- 1990 April
Microsoft introduces Russian MS-DOS 4.01 for the Soviet market. May
Digital Research releases DR DOS 5.0.
--- 1991 June
Microsoft releases MS-DOS 5.0. It adds a full-screen editor, undelete and unformat
utilities, and task swapping.
GW-BASIC is replaced with Qbasic, based on Microsoft's QuickBASIC. September
Digital Research Inc. releases DR DOS 6.0, for US$100.
--- 1993 March
Microsoft introduces the MS-DOS 6.0 Upgrade, including DoubleSpace disk compression.
1 million copies of the new and upgrade versions are sold through retail channels
within the first 40 days. November
Microsoft releases MS-DOS 6.2.
--- 1994 February
Microsoft releases MS-DOS 6.21, removing DoubleSpace disk compression. April
IBM releases PC-DOS 6.3. June
Microsoft releases MS-DOS 6.22, bringing back disk compression under the name
--- 1995 February
IBM announces PC DOS 7, with integrated data compression from Stac Electronics
IBM releases PC DOS 7.
In August of 1995 Microsoft introduces Windows 95,
it includes MS DOS 7.0 but it's clear that DOS is going to die a slow