Timeline 1980-1993

A History of Microsoft MS-DOS and Windows (and its main competitors) on the 8086 Processor family

NOTE - Other (minor) versions of DOS & Windows exist, This list is based on major versions plus items observed or reported
Updates other than NT Service Packs are available via the PowerLoad Resource Pages

Month	Year	Version	Major Changes or Remarks
December	1980	QDOS	Microsoft buys non-exclusive rights to market Pattersons Quick & Dirty Operating System from Seattle Computer Products (Developed as 86-DOS) (Which is a clone of Digital Researches CP/M in virtually every respect)
July	1981	86-DOS	Microsoft buys all rights to 86-DOS from Seattle Computer Products, and the name MS-DOS is adopted for Microsoft's purposes and IBM PC-DOS for shipment with IBM PCs (For Computers with the Intel 8086 Processor)
Q3	1981	CP/M 86	Digital Research release CP/M 86 for the Intel 8086 Processer
Mid	1981	PC-DOS 1.0	Pre-Release PC-DOS produced for IBM Personal Computers (IBM PC) Supported 16K of RAM, ~ Single-sided 5.25" 160Kb Floppy Disk
August	1982	PC-DOS 1.1	OEM PC-DOS for IBM Corporation. (First Release Version)
September	1982	MS-DOS 1.25	OEM Version for Zenith Computer Corporation.. (Also known as Z-DOS) This added support for Double-Sided 5.25" 320Kb Floppy Disks. Previously the disk had to be turned over to use the other side
Q4	1982	CP/M Plus	Digital Research release CP/M Plus for the Intel 8086 Processer
March	1983	MS-DOS 2.0	OEM Version For Zenith - This added support for IBM's 10 MB Hard Disk, Directories and Double-Density 5.25" Floppy Disks with capacities of 360 Kb
March	1983	PC-DOS 2.0	OEM PC-DOS for IBM Corporation. - Released to support the IBM XT
March	1983	MS-DOS GUI	Microsoft first announces it intention to create a GUI (Graphical User Interface) for its existing MS-DOS Operating System. Microsoft also introduces its first mouse, "The Microsoft Mouse", including card and software, for US$200. A major tool in its GUI Development Program. (Windows is Born)
November	1983	MS-DOS 2.01	OEM Version for Wang Computer Corporation.
November	1983	PC-DOS 2.1	OEM PC-DOS for IBM Corporation. - Released to support IBM PCjr PC
November	1983	Microsoft Windows for MS-DOS	Microsoft formally announces Windows 1.0, but does not have a working copy! Microsoft shows Windows to IBM, but IBM is not interested in such an unfinished product.
November	1983	Digital Research	*Meanwhile,* Digital Research debuts its GEM GUI for the IBM PC at Fall COMDEX 1983, and also debuts its first multiuser and multitasking version of CP/M, Concurrent CP/M (MP/M) for the Intel-based IBM PC.
December	1983	MS-DOS 2.11	OEM Version for AT&T, Bull & Sony. - Support for foreign and extended characters was added.
Notes	>>>>	"DOS Menu"	There were also a number of Retail/Freeware Menu or Shell Programs becoming available for DOS to help the novice user and shield him from the 'raw' command line! Prompting Microsoft to speed up its GUI development work!
Early	1984	MS-DOS 2.25	OEM Version for Unknown Computer Manufacture. (Possibly Zenith)
September	1984	MS-DOS 3.0	OEM Version for Various Manufactures.- Support for High-Density 1.2 MB Floppy Disks and 32 MB Hard Disks was added. - No extended partitions.
September	1994	PC-DOS 3.0	OEM PC-DOS for IBM Corporation
November	1984	MS-DOS 3.1	OEM Version for Various Manufactures. Network support was added.
>	1985	DOSPlus 1.0	Digital Research release DOSPlus 1.0 as a follow on from CP/M Plus
March	1985	Dr GEM 1.1	A small number of Computer Manufactures start to bundle 'GEM' DOS Manager by Digital Research (Who also published DR-DOS) It stands for Graphical Environment Manager Details & History
September	1985	Dr GEM 1.2	Digital Research release 'retail' GEM version 1.2
November	1985	Microsoft Windows 1.01	Microsoft announces the Retail shipment of Microsoft Windows, a GUI which extends the features of the DOS operating system. Windows provides users with the ability to work with several programs at the same time and easily switch between them without having to quit and restart individual applications. (Retail Price was US$99) Screenshots
December	1985	PC-DOS 3.2	OEM PC-DOS for IBM Corporation. ~ Support for 3.5" LD 720Kb Floppy Disks
>	1986	DOSPlus 2.0	Digital Research release DOSPlus 2.0 - Forerunner to DrDOS
>	1986	*Dr GEM*	Amstrad & KayPro bundle 'GEM' software with MS-DOS 3.1
April	1986	MS-DOS 3.2	First Retail Release of MS-DOS ~ Support for 3.5" LD 720Kb Floppy Disks
August	1986	Windows 1.03	Microsofts second release, - MS-DOS version 3.2 support added
January	1987	Windows DDL Volume 1	Microsoft Windows Device Driver Library Volume 1 Additional support for display devices, printers, and pointing devices added
April	1987	OS/2	Microsoft announces MicroSoft Operating System/2 (MS OS/2) a new personal computer operating system. It has been designed and developed specifically to harness the capabilities of personal computers based upon the Intel 80286 and 80386 microprocessors. This is the first product to be announced as a result of the Joint Development Agreement between IBM and Microsoft announced in August 1985. - Intended Replacement for MS-DOS
April	1987	Windows 1.04	- IBM Personal System/2 support added
April	1987	MS-DOS 3.21	OEM Version for Kaypro & Zenith Computer Corporations. (And others)
April	1987	MS-DOS 3.3	MS-DOS 3.3 introduces support for more than one logical drive per hard disk. Logical drives are treated as completely separate disks under MS-DOS, even though they may occupy the same physical hard disk. Plus 3.5" HD 1.44MB Floppy Disk Support + Real Time Support for the 'new' CMOS clock
April	1987	PC-DOS 3.3	OEM PC-DOS for IBM Corporation. Added support for PS/2 Computers
April	1987	MS OS/2 - 1.0	Microsoft & IBM OS/2 Version 1.0 Released Click here for OS/2 History, Sub-Versions and Resources
Mid	1987	DOSPlus 2.1	Digital Research release DOSPlus 2.1 - Last release before DrDOS 3.31
October	1987	MS LAN Manager	Microsoft releases LAN Manager, (Local Area Network) a LAN operating system add-on that runs on both MS-DOS and OS/2.
November	1987	Windows 2.0	Microsoft releases Microsoft Windows 2.03 (Retail Packaging however may show it as Windows 2.0) offering compatibility with existing Windows applications and a new visual appearance compatible with Microsoft OS/2 Presentation Manager. In addition to the new visual appearance, it uses a system of overlapping windows, rather than tiled windows. Windows 2.03 also includes significant performance enhancements and improved support for expanded memory hardware. Screenshots
>	1988	Windows/286	Version 2.03 ~ When Windows/386 was released, Microsoft renamed Windows 2.03 to Windows/286 (For the Intel 286) for version consistency, And labelled all further production accordingly. However it was not replaced by Windows/386, As both versions were aimed at different processors. Therefore Version 2.03 can be found labelled under both descriptions.
February	1988	MS-DOS 3.3Plus	Extended MS-DOS for Selected OEMs
March	1988	MS-DOS 3.3T	Modified MS-DOS 3.3 for Tandy (Radio Shack) Computers as TandyDOS
April	1988	MS-DOS 3.31	Extended Version for Various OEM Manufactures.
May >	1988	DrDOS 3.3x	Digital Research release DrDOS 3.31 (No version 3.0 recorded) followed by a series of OEM versions. 3.32, 3.33, 3.34, 3.35, 3.40, 3.41 & 3.42 Some releases include a version of GEM Desktop (Called ViewMAX)
July	1988	MS-DOS 4.0	This version provided XMS support, support for partitions on hard disks up to 2.10 GB and a graphical shell. ~ It also contained a large number of bugs and many programs refused to run on it.
July	1988	PC-DOS 4.0	OEM PC-DOS for IBM Corporation. (IBM buy rights to future versions of PC-DOS)
August	1988	Windows/286	Version 2.10 ~ Intel 286 Optimised Edition
August	1988	Windows/386	Version 2.10 ~ Intel 386 Optimised Edition (Introduces HIMEM.SYS Driver)
October	1988	MS OS/2 1.10	Microsoft and IBM announce the delivery of the jointly developed Operating System/2 (OS/2) 1.1 with Presentation Manager. Presentation Manager is the graphical user interface (GUI) for the OS/2 operating system. This is the second major release of the Standard Edition of OS/2. *(LAN version also released)*
November	1988	MS-DOS 4.01	Major Bug Fix for MS-DOS 4.0 (Core Files almost completely rewritten)
November	1988	PC-DOS 4.01	Major Bug Fix for PC-DOS 4.0
December	1988	DrDOS 4.41	Digital Research release DrDOS 4.41 (No Version 4.0 released!)
March	1989	Windows/286	Version 2.11 ~ Intel 286 Optimised Edition
March	1989	Windows/386	Version 2.11 ~ Intel 386 Optimised Edition
April	1989	MS-DOS 4.01a	Minor update to MS-DOS 4.01 to include better support as Larger Hard Drives become available. A File Update is also released to support MS-DOS 4.01
April	1989	Dr GEM 3.13	Last retail release of GEM by Digital Research
April	1989	MS OS/2 - 1.10EE	Microsoft and IBM OS/2 1.10 Extended Edition released, with LAN Manager.
June	1989	IBM OS/2 - 1.20	IBM OS/2 1.20 released.
May	1990	Windows 3.0	Microsoft announces the immediate, worldwide availability of Microsoft Windows 3.0, This version offers dramatic performance increases for Windows applications, advances in ease of use and aesthetic appeal, and straightforward integration into corporate computing environments Network Drivers also made available. Screenshots IBM start to offer Windows 3.0 as a PS/2 Option
May	1990	DrDOS 5.0	Digital Research release DrDOS 5.0 - First Retail Version
September	1990		IBM and Microsoft agree to end their development relationship.
April	1991	IBM OS/2 - 1.30	IBM OS/2 1.30 released.
October	1991	Windows 3.0a	Maintenance Release of Windows 3.0 focusing on specific problems
April	1991	MS-DOS 5.0	This was a major upgrade. It allowed parts of DOS to load itself in the high memory area and certain device drivers and TSRs to run in the unused parts of the upper memory area between 640K and 1024K. This version also added support for IBM's new 2.88 MB floppy disks. An improved BASIC interpreter and text editor were included, as was a disk cache, an undelete utility and a Hard Disk partition-table backup program . After the problems with MS-DOS 4, it also provided a utility to make programs think they were running on a different version of MS-DOS.(SETVER) ~ Restores confidence in DOS after v4.x disaster.
June	1991	DrDOS 6.0	Digital Research release DrDOS 6.0 Adds disk compression, disk optimizer, etc.
June	1991	PC-DOS 5.0	IBM PC-DOS 5.0
June	1991	MS-DOS 5UG	MS-DOS 5.0 Upgrade Edition for all earler versions (First Upgrade Version)
October	1991	Windows 3.0 with Multimedia Extensions Version 1.0	OEM Windows 3.0 with MultiMedia Extensions v1.0. This version of Windows was probably a standard version of Windows 3.0a and Microsoft Multimedia Extensions Version 1.0 being released as an OEM Multimedia CD-ROM only. IBM list Windows 3.0 MM as an option for PS/2 Computers
Notes	1991	Tandy Modular Windows	Tandy Modular Windows was an OEM Special GUI for Tandy Corp.'s Video Information System (VIS) Multimedia Player. It was essentially a Windows 3.0 Core Program, But without any Microsoft Desktop Accessories, Drivers, or a number of other features. (Not to be confused with Windows 3.0 MultiMedia)
Q3	1991	Windows NT Program	New Technology Development Program - NT Operating System was first intended to be based on OS/2 Technology but was later changed to Windows
Q4	1991	MS-DOS 5.Oa	This was a minor update for MS-DOS 5.0 which dealt with possibly catastrophic problems with UNDELETE and CHKDSK. A File Update is also released
Q4	1991	MS-DOS 5aUG	Replaces MS-DOS 5.0 Upgrade (Details as for MS-DOS 5.0a)
February	1992	PC-DOS 5.0.1	PC-DOS 5.0 Rev 1 (Possibly an update for same reason as MS-DOS 5.0a)
April	1992	Windows 3.1	Microsoft ships Microsoft Windows 3.1 with over 1,000 enhancements. The new version created unprecedented user demand with over one million advance orders placed worldwide. ~ 386 Enhanced Mode with minimum 4MB RAM - Operates in Standard Mode with 2MBs - Added support for Truetype Fonts Screenshots
April	1992	Win 3.1UG	Windows 3.1 Upgrade for Windows 3.0 Users. (Full Version marked Upgrade!)
June	1992	IBM OS/2 - 2.0	IBM OS/2 version 2.0 released. (Microsoft withdraws support for OS/2)
September	1992	PC-DOS 5.0.2	PC-DOS 5.0 Rev 2 - To correct errors with Windows 3.1 (EMM386.EXE)
October	1992	Windows for Workgroups 3.1 (WfWG 3.1)	Microsoft announces the worldwide availability of Microsoft Windows for WorkGroups 3.1 (WfWG) which integrates networking and workgroup functionality directly into Windows 3.1. The product allows common activities of sending electronic mail, scheduling group meetings, sharing files and printers, managing calendars, and working together on groups projects. It can provide networking capabilities on its own, or it can be used as a client on an existing local area network. Screenshots *(Unlike* NT, WfWG is still a MS-DOS GUI)
October	1992	WfWG31AD	Windows for Workgroups 3.1 Add-On for MS-DOS Users
October	1992	WfWG31AW	WfWG 3.1 Add-On for Windows Users - This package is for machines that already have Windows version 3.1 installed. It upgrades Windows by adding those files required for the new features of WfWG 3.1 (Uses Compliance Checking)
Q4	1992	WindowsNT BETA	Windows New Technology - First BETA Testing of Windows NT ~ Microsofts first true 32bit Operating System.
March	1993	MS-DOS 6.0	This was a catch-up with Novell's DR-DOS 6. It added a disk-compression utility called DoubleSpace, a basic anti-virus program and a disk defragmenter. It also finally included a MOVE command, an improved backup program, MSBACKUP and multiple boot configurations. Memory management was also improved by the addition of MEMMAKER. A number of older utilities, such as JOIN and RECOVER were removed. However DOSSHELLwas still included.
March	1993	MS-DOS6UG	MS-DOS 6.0 Upgrade Edition for all earler versions from 3.3 onwards.
March	1993	6.0 Supplemental	Microsoft released a Supplemental Update of Earler Files removed from v6.0
May	1993	Windows for PEN Computing 3.1	Microsofts first attempt at a GUI for Palm and Organiser type small computers. It used a cut down version of MS-DOS 6.0 & Windows 3.1 with a PEN Driver Set.
Note	1993	Dr PalmDOS	Digital Research base their PalmDOS on CP/M with GEM ViewMAX
June	1993	PC-DOS 6.1	IBM starts to number PC-DOS in series with MS-DOS
Q3	1993	NovellDOS 7.0	DrDOS sold to Novell who release it as NovellDOS 7.0 with NetWare
July	1993	WindowsNT 3.1	Windows NT - Designed for Business & Networking Use - Not dependent on MS-DOS - Uses its own NTFS Bootstrap to install. (Released on 3.5" Disks) Link Site Abandoned - New Screenshots to Follow
>	>	Windows NT Service Packs	After the release of NT 3.1 Microsoft began a series of Service Pack Releases, which included Updates, Patchs as well as New or Updated Network Drivers. The Last known Service Pack for Windows NT 3.1 was SP-3 (Dated October 1994)
November	1993	MS-DOS 6.2	Extra security was built into DoubleSpace following complaints of data loss. A new disk checker, SCANDISK, was also introduced, as well as improvements to DISKCOPY and SmartDrive (DOSSHELL was removed to the Supplemental Disk Set)
November	1993	MS-DOS62UG	MS-DOS 6.2 Upgrade Edition for all earler versions from 3.3 onwards.
November	1993	MS-DOS62SU	MS-DOS 6.2 Step-Up for 6.0 Users Only (MS-DOS Step-Up differs from Upgrade in that it is limited to earler 6x versions only and contains file updates not complete copies of application files other than IO.SYS & MSDOS.SYS)
November	1993	6.2 Supplemental	Microsoft released a Supplemental Update of Earler Files removed from v 6.2 Including DOSSHELL which was removed from 6.2 & later versions.
December	1993	Windows for Workgroups 3.11 (WfWG 3.11)	WfWG 3.11 contains the complete software package for machines that do not have Windows Operating System version 3.0 or 3.1. It contains all the WfWG software, including Windows 3.1 functionality, file sharing, printer sharing, network dynamic data exchange (DDE), Microsoft Mail, Microsoft Schedule+, Microsoft At Work PC Fax, Remote Access Services, 32-bit file and disk access, and advanced security. Screenshots
December	1993	WfWG311AD	WfWG 3.11 Add-On for MS-DOS Users.
December	1993	WfWG311AW	WfWG 3.11 Add-On for Windows Users -This package is for machines that already have Windows or WfWG version 3.1 installed. It upgrades Windows or WfWG 3.1 by adding those files required for the new features of WfWG 3.11.
December	1993	MSClient 3.0	Microsoft Client for MS-DOS version 3.0 (Network Add-On for MS-DOS)
December	1993	Windows 3.11	With WfWG Compatable Core Files, SVGA & updated drivers Screenshots Windows 3.11 was never marketed as such, It is a Service Release of Windows 3.1 only - The only way to check you have it was to click the 'About' Box
December	1993	Win31 Updates	Microsoft also made available 2 updates for Windows 3.1 to bring it upto Windows 3.11 standard ~ 3.11 Core Files and SVGA Driver Updates.
December	1993	PC-DOS 6.3	Replaces PC-DOS 6.1

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