Chronology of Personal Computer Software

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Last updated: 2022 April 29.


  • Bob Frankston creates the data interchange format (DIF) for VisiCalc. [1056.328]
  • Microsoft acquires a license for UNIX source code from AT&T. [1149.155]
  • Microsoft begins development on an 8086 version of AT&T's UNIX operating system. It will emerge as XENIX. [346.74]
  • Apple Computer releases Apple FORTRAN software for the Apple II. [1886.65]
  • At the West Coast Computer Faire, Microsoft announces its first hardware product, the Z-80 SoftCard for the Apple II. This card, incorporating a Zilog Z-80 processor, gives the Apple II CP/M capability, contributing greatly to Apple Computer's success. The card includes CP/M and Microsoft's Disk BASIC, all for US$349. Tim Patterson of Seattle Computer Products had built several prototypes before Microsoft's Don Burdis took over the project. The "Z-80" part of the name is later dropped at Zilog's request. [9] [252.47] [266.269] [346.65] [1299.137] (April [123])
(month unknown)
  • Microsoft negotiates a license for CP/M from Digital Research for US$50,000 cash, for distribution with the SoftCard. [1299.138]
  • 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. Tim Patterson begins work on the project. (The resulting 86-DOS will be bought by Microsoft for use on the IBM PC.) [2] [346.75] [979] [1149.183] [1299.157]
(month unknown)
  • Wayne Ratliff contracts with George Tate to market his Vulcan database program. [618.262]
  • Logo Computer Systems is formed in Montreal, Canada, to market the public domain language LOGO. [615.119]
  • Microsoft begins work on its first microcomputer application, a spreadsheet program initially called Electronic Paper. (It will be released as Multiplan.) [346.104] [1299.185]
  • Ken and Roberta Williams start On-Line Systems, developing software for the Apple II. First game released is Mystery House. [353.282] [1532.10]
  • Sierra On-Line releases the Mystery House game. [1474.77]
  • Sierra On-Line releases the Wizard & The Princess game. [1474.77]
  • Atari releases a Pascal compiler for the Atari 400 and 800. Price is US$50. The compiler supports both P-Code and native code. [1167]
  • Microsoft announces the Microsoft XENIX OS, a portable and commercial version of the UNIX operating system for the Intel 8086, Zilog Z8000, Motorola M68000, and Digital Equipment PDP-11. [123] [258.252] [259.6] [369.24] [1186.25] (February [1149.155])
  • Apple Computer releases DOS 3.3. [218]
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August 21
  • IBM meets with Microsoft again, to talk in general terms about their planned personal computers. IBM asks if Microsoft will develop some programming language interpreters/compilers for it. Bill Gates agrees to supply BASIC and other software development tools. IBM also asks for CP/M, but Gates says Digital Research would have to supply that. [266.271] [346.71] [906.469] [1149.171] [1299.153] [2324.106]
  • Bill Gates calls Gary Kildall, to arrange a meeting between IBM and Digital Research regarding CP/M. [1299.153] (September [1149.179])
August 22
  • IBM's Project Chess task force meets with Digital Research about using CP/M-86 for IBM's upcoming microcomputer. (Gary Kildall claims he agreed to provide CP/M-86 for IBM. IBM sources state that Gary Kildall was not interested.) [346.74] [620.110] [1299.155] [2324.106] (September [1149.179])
August 28
  • IBM representatives meet at Microsoft again. Bill Gates signs a consulting agreement for US$15,000 to develop the software specifications for IBM's personal computer. Jack Sams asks about alternatives to CP/M-86. Gates says he might find one. [266.272] [1299.156] [2324.107] (July [185.125]) (September [346.75]) (Microsoft proposes it to IBM [346.75])
  • Seattle Computer Products completes and begins shipping 86-QDOS 0.10 (Quick and Dirty Operating System). Even though it had been created in only two man-months, the DOS worked surprisingly well. (A week later, the EDLIN line editor is created. EDLIN was supposed to last only six months, before being replaced.) [2] [1149.183] (SCP-DOS [266.272])
  • Tim Patterson, of Seattle Computer Products, shows Microsoft his operating system written for the 8086 processor. [346.260]
  • Software Publishing ships the pfs:File database program. [346.261]
September 22
  • Paul Allen of Microsoft contacts Rod Brock of Seattle Computer Products, asking to sub-license 86-DOS to a potential customer. [1149.185] [1299.160]
September 28
  • At Microsoft, Bill Gates, Paul Allen and Kay Nishi make the final decision to accept the IBM contract to produce languages and an operating system for the new microcomputer. [1149.186]
September 30
  • Bill Gates, Bob O'Rear, and Steve Ballmer meet with IBM in Boca Raton, Florida, to deliver a report to IBM. They propose that Microsoft be put in charge of the entire software development process for IBM's new microcomputer, including providing the main operating system to run on the computer. Bill Gates insists on maintaining rights to the DOS, receiving royalty payments rather than a lump sum. [266.272] [346.73,76] [1299.161] (October [1149.188])
  • 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. [346.76]
November 6
  • Microsoft and IBM sign a formal contract for Microsoft to develop certain software products for IBM's new microcomputer. Microsoft will receive US$200,000 to adapt the operating system to the IBM PC, and US$500,000 for DOS, BASIC, and compilers. Microsoft is to have an initial version of the operating system and BASIC working by mid-January. [41] [266.273] [346.77] [1149.190] [1299.163] [1701.158]
  • The Congress of the US passes the Computer Software Copyright Act of 1980. [1337.D1]
November (month)
  • Top selling Tandy TRS-80 computer game for the month: Hellfire Warrior. [2649.17]
(month unknown)
  • Digital Research releases CP/M-86 for Intel 8086- and 8088-based systems. [255.200]
  • Richard Garriott releases the Ultima I fantasy role-playing game for the Apple II computer in the US. [1175.55] [1688.116]
  • InfoCom releases the Zork adventure game for the TRS-80 and Apple II. (In the first nine months, 7,500 copies are sold.) [548.436] [809]
  • Seattle Computer Products renames QDOS to 86-DOS, releasing it as version 0.3. [2] [1299.158]


January 6
  • Microsoft and Seattle Computer Products sign a licensing agreement giving Microsoft a non-exclusive right to market 86-DOS. SCP receives US$10,000 for signing, US$10,000 per sublicense through Microsoft, and US$5,000 if source code is part of the sublicense. [2] [1149.194] [1299.169]
  • MT MicroSYSTEMS wins a contract (over Microsoft) from Intel to develop a custom 8086 implementation of Pascal/MT+. [1167]
  • Microsoft operates 86-DOS for the first time on IBM's prototype microcomputer. [346.81] [1149.196] (January [1299.169])
  • At the West Coast Computer Faire, MT MicroSYSTEMS releases the Pascal/MT+ SpeedProgramming Package for CP/M-80, price US$500, including compiler. This is a specialized Pascal source code editor with syntax sensitive editing. [1167]
June 25
  • Paul Allen of Microsoft proposes to Rod Brock of Seattle Computer Products that Microsoft buy all rights to 86-DOS for US$30,000 plus a free license to Microsoft's 8086 macro assembler and linker. [1299.174]
  • Microsoft completes most work on 86-DOS for IBM's PC. [1149.199]
(month unknown)
  • Sir-Tech Software releases the fantasy role-playing game Wizardry: Proving Grounds of the Mad Overlord for the Apple II. [1175.55]
  • Eddie Curry of LifeBoat Associates offers Rod Brock of Seattle Computer Products US$250,000 for the rights to 86-DOS. Brock can not accept the offer, as Microsoft has an excusive license to sell 86-DOS. [1149.201]
  • Sierra On-Line releases the Mission Asteroid game. [1474.77]
  • Doug and Gary Carlston form Broderbund, and begin selling their first game, Galactic Saga for the TRS-80. [1532.10]
July 10
  • Rod Brock of Seattle Computer Products offers a counterproposal to Microsoft for rights to 86-DOS: US$150,000 fee and right to license Microsoft languages at a discount with SCP hardware. [1299.174]
July 21
  • Digital Research's Gary Kildall tells IBM that its PC-DOS software infringes his CP/M copyright. He says he will not sue if IBM sells CP/M on the IBM PC in addition to PC-DOS. [2324.107]
July 27
  • Microsoft buys all rights to 86-DOS from Seattle Computer Products for US$50,000, and the name MS-DOS is adopted. Microsoft agrees to give SCP generous terms for licensing its languages. [2] [31] [146] [1149.201] [1299.175]
August 12
  • IBM introduces the Microsoft Adventure game for the IBM PC, Microsoft's first non-language non-OS software product. [1149.205]
  • Microsoft begins work on a graphical user interface for MS-DOS, initially called Interface Manager, because it would effectively hide the interface between programs and devices like printers and video cards. (This is the beginning of Windows.) [346.175] [1648.51]
  • Logo Computer Systems of Canada completes a contract with Apple Computer, for Apple to distribute their version of the LOGO language. This is the first time Apple agrees to co-label a product with an outside supplier, and the first time Apple signs a contract with a supplier outside of the US. [615.120]
  • The 200,000th copy of VisiCalc is sold. [1299.184]
  • Hitachi licenses GW-BASIC from Microsoft. "GW" stands for Gee Whiz. This is Microsoft's first US$1 million single product licence. [1299.193]
  • Ashton-Tate ships the dBase II database program. [41] (January [346.261])
(month unknown)
  • Microsoft begins upgrade work on DOS 1.1. [1149.215]
  • Microsoft releases Microsoft BASIC v5, known as GW-BASIC. [949.300] (1982 spring [346.262])

End of 1980-1981. Next: 1982.
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1990 1991 1992-1993 1994-1995 1996-1997 1998-1999 2000-2001 2002-2003 2004 2005

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