December, 1980 - QDOS July, 1981 - 86-DOS Q3, 1981 - CP/M 86 Mid, 1981 - PC-DOS 1.0 August, 1982 - PC-DOS 1.1 September, 1982 - MS-DOS 1.25 http://oldfiles.org.uk/powerload/timeline.htm

http://en.wikipedia.org/wiki/MS-DOS 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 drives. 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. --- 1988 Digital Research transforms CP/M into DR DOS. June Microsoft releases MS-DOS 4.0, including a graphical/mouse interface. July 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 DriveSpace. --- 1995 February IBM announces PC DOS 7, with integrated data compression from Stac Electronics (Stacker). April 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 death.