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Windows 3.1x is a series of 16-bit operating systems, produced by Microsoft for use on personal computers. The series began with Windows 3.1, which was first sold during March 1992 as a successor to Windows 3.0. Subsequent versions were released between 1992 and 1994 until the series was superseded by Windows 95. During its lifespan, Windows 3.1 introduced various enhancements to the still MS-DOS-based platform, including improved system stability, expanded support for multimedia, TrueType fonts, and workgroup networking.
Windows 3.1 was originally released on April 6, 1992; official support for the Windows 3.1 family ended on January 1, 2002, and OEM licensing for Windows for Workgroups 3.11 on embedded systems continued to be available until November 1, 2008.
Windows 3.1 (originally codenamed Janus, of which two betas were published), released on April 6, 1992, includes a TrueType font system (and a set of highly legible fonts), which effectively made Windows a viable desktop publishing platform for the first time. Similar functionality was available for Windows 3.0 through the Adobe Type Manager (ATM) font system from Adobe.
Windows 3.1 was designed to have backward compatibility with older Windows platforms. As with Windows 3.0, version 3.1 had File Manager and Program Manager, but unlike all previous versions, Windows 3.1 and later support 32-bit disk access, cannot run in real mode, and included Minesweeper instead of Reversi (though Reversi was included in some copies).
Windows 3.1 Multimedia PC Version (Beta only, released Nov 1992 – codenamed Bombay) included a media viewer, and the ability to play video files. It was targeted to the new multimedia PC and included sound and video integration with CD-ROM support.
Improvements over Windows 3.0
Windows 3.1 dropped real mode support and required a minimum of a 286 PC with 1MB of RAM to run. The effect of this was to increase system stability over the crash-prone Windows 3.0. Some older features were removed like CGA graphics support (although the Windows 3.0 CGA driver will still work on 3.1) and compatibility with real mode Windows 2.x applications.
Windowed DOS applications (in enhanced mode) gained the ability for users to manipulate menus and other objects in the program using the Windows mouse pointer (provided that the DOS application supported mice). A few DOS applications such as late releases of Microsoft Word can access the Windows Clipboard. Windows' own drivers cannot directly work with DOS applications; hardware such as mice require a DOS driver to be loaded before starting Windows.
Icons could be dragged and dropped for the first time in addition to looking more detailed. A file could be dragged onto the Print Manager icon and the file would be printed by the current printer, assuming it was associated with an application capable of printing, such as a word processor. Alternatively, the file could be dragged out of the File Manager and dropped onto an application icon or window for processing.
In 386 enhanced mode, Windows 3.1 can theoretically access up to 4GB of RAM (no single application can use more than 16MB) although it is limited to 64MB because of the way it detects the amount of RAM installed in the computer (this is most likely due to the use of INT 12h memory detection techniques, which is limited to showing 65535KB of RAM). The File Manager was significantly improved over Windows 3.0. Most significantly, Windows 3.1 added multimedia support for the first time.
Windows 3.1 was the first version of Windows to be distributed on CD-ROM (although this was more common for Windows for Workgroups 3.11, which typically came with DOS 6.22 on one CD) in addition to 720k, 1.2MB, and 1.44 MB floppy distributions. Installed size on the hard disk was between 10 and 15MB.
32-bit disk access (386 enhanced mode only) brought improved performance by using a 32-bit protected mode driver instead of the 16-bit BIOS functions (which necessitate Windows temporarily dropping out of protected mode).
Windows 3.1 also introduced the Registry, a centralized database that can store configuration information and settings for various operating systems components and applications.
Windows 3.1 for Central and Eastern Europe
A special version named Windows 3.1 for Central and Eastern Europe was released that allowed the use of Cyrillic and had fonts with diacritical marks characteristic of Central and Eastern European languages. Microsoft introduced its own codepage (Windows-1250) and supported its use in violation of many countries' ISO standards (e.g., the official Polish codepage is ISO-8859-2, which was ignored by Microsoft but is supported by contemporary Internet Explorer versions). Similarly, Microsoft also released Windows 3.1J with support for the Japanese language, which shipped 1.46 million copies in its first year on the market (1993) in Japan.
Modular Windows is a special version of Windows 3.1, designed to run on the Tandy Video Information System.
On August 11, 1993, Microsoft released an update for Windows 3.1 known as Windows 3.11. Thus, Windows 3.11 is not a standalone version of Windows, but rather a software update from Windows 3.1, much like modern Windows service packs. For those who did not own Windows 3.1, full disk sets of Windows 3.11 were available at the time.
On November 22, 1993, Microsoft released a Simplified Chinese version of Windows for the Chinese market. The updated system identified itself as Windows 3.2. Thus, Windows 3.2 is the Chinese version of Windows 3.11. The update was limited to this language version, as it fixed only issues related to the complex writing system of the Chinese language.
Windows 3.2 was generally sold by computer manufacturers with a ten-disk version of MS-DOS that also had Simplified Chinese characters in basic output and some translated utilities.
Windows for Workgroups
Windows for Workgroups is an extension that allowed users to share their resources and to request those of others without a centralized authentication server. It used the SMB protocol over NetBIOS.
Windows for Workgroups 3.1
Windows for Workgroups 3.1 (originally codenamed Winball and later Sparta), released in October 1992, features native networking support. Windows for Workgroups 3.1 is an extended version of Windows 3.1 that comes with SMB file sharing support via the NetBIOS based NBF and/or IPX network transport protocols, includes the Hearts card game, and introduced VSHARE.386, the Virtual Device Driver version of the SHARE.EXE Terminate and Stay Resident program.
Windows for Workgroups 3.11
Windows for Workgroups 3.11 (originally codenamed Snowball) was released on August 11, 1993, and shipped in November 1993. It supported 32-bit file access, full 32-bit network redirectors, and the VCACHE.386 file cache, shared between them. WFW 3.11 dropped standard mode support and requires a 386 machine to run.
A Winsock package was required to support TCP/IP networking in Windows 3.x. Usually third-party packages were used, but in August 1994, Microsoft released an add-on package (codenamed Wolverine) that provided TCP/IP support in Windows for Workgroups 3.11. Wolverine was a 32-bit stack (accessible from 16-bit Windows applications via WinSock Thunk), which gave it superior performance to most of the third-party TCP/IP Windows stacks available. However, it was only compatible with Windows for Workgroups 3.11, and lacked support for dial-up. The Wolverine stack was an early version of the TCP/IP stack that would later ship with Windows 95, and provided an early testbed for the 16-to-32-bit compatibility layer that was crucial to Windows 95's success.
Following the release of DOS 6.22 in 1994, WFW 3.11 largely replaced Windows 3.1 for OEM installations on new PCs due to its improved capabilities and greater stability.
Video for Windows
Video for Windows was first introduced in November 1992 as a reaction to Apple Computer's QuickTime technology which added digital video to the Macintosh platform. Costing around $200, the software included editing and encoding programs for use with video input boards. A runtime version for viewing videos only was also made available. Originally released as a free add-on to Windows 3.1 and Windows 3.11, it then became an integral component of Windows 95 and later. Like QuickTime there were three components in Video for Windows. The technology introduced a file format designed to store digital video, Audio Video Interleave (AVI). The technology provided an application programming interface that allowed software developers working on the Windows platform to add the ability to play or manipulate digital video to their own applications. Lastly, it included a suite of software for playing and manipulating digital video.
Windows for Pen Computing
Windows for Pen Computing was a series of Microsoft-produced add-ons for Microsoft Windows versions in the mid-1990s with additional tools for tablet PCs. Windows for Pen Computing (also known as Pen Windows and W4PC) was developed as Microsoft's Pen computing response to the PenPoint OS by GO Corporation. Windows for Pen Computing was rendered obsolete by the Tablet PC support for Windows XP Tablet PC Edition in 2002.
Windows 3.1x was given limited compatibility with the then-new 32-bit Windows API used by Windows NT by another add-on package, Win32s. There was a rumor that Microsoft did not want to increment any mainstream Windows 3.1x version to something like "Windows 3.2" because it could be confused with the Win32 API or otherwise distract consumers from upgrading to a "real 32-bit OS" like the then-upcoming Windows 95 was, though Windows NT 3.1 and 3.5 were both 32-bit operating systems that looked similar in appearance. For testing of the new Win32s functions the game FreeCell was included.
Windows 3.1x introduced new possibilities for applications, especially multimedia applications. During this era, Microsoft developed a new range of software that was implemented on this operating environment, called Microsoft Home, Microsoft Bob being one of the programs.
As the first versions of Windows to enjoy major commercial success and software support, Windows 3.1 and WFW 3.11 quickly replaced DOS as the platform for application software on PC compatibles. Multimedia software (especially games) proliferated, although many games continued to run on DOS until Windows 95.
Program Manager was included in all versions of Windows from version 3.0 until Windows XP Service Pack 1. A non-operable icon library named progman.exe is included in Windows XP Service Pack 2, and the file was removed entirely from Windows Vista.
If Program Manager is started under Windows XP Service Pack 2 and later, it does not appear to run, but when a .grp file created for Windows 3.1 is processed, it converts the .grp file contents to a Start Menu folder.
Microsoft released versions of Internet Explorer from 2.0 up to the first release of version 5.0 for Windows 3.1.
Promotion and reception
Microsoft began a television advertising campaign for the first time on March 1, 1992. The advertisements, developed by Ogilvy & Mather, were designed to introduce a broader audience to Windows. Windows 3.1 was shipped worldwide on April 6, 1992, and reached three million sales two months later. The year of Windows 3.1's release was successful for Microsoft, which was named the "Most Innovative Company Operating in the U.S." by Forbes Magazine, while Windows became the most widely-used GUI-based operating environment.
The installer to the beta release used code that checked whether it was running on Microsoft-licensed DOS or another DOS operating system (such as DR-DOS). The code ran several functional tests that succeeded on MS-DOS and IBM PC DOS, but resulted in a technical support message on competing operating systems. If the system was not MS-DOS, the installer would fail. Digital Research, who owned DR-DOS, released a patch within weeks to allow the installer to continue. Microsoft disabled, but did not remove, this warning message for the final release of Windows 3.1. When Caldera bought DR-DOS from Novell, they brought a lawsuit against Microsoft over the AARD code, which was later settled.
Windows 3.x was superseded by the release of Windows 95 in August 1995. Microsoft officially dropped support for all 16-bit versions of Windows on December 31, 2001.
Windows 3.1 found a niche market as an embedded operating system after becoming obsolete in the PC world. As of November 2008, both Virgin Atlantic and Qantas employed it for some of the onboard entertainment systems on long-distance jets. It also sees continued use as an embedded OS in retail cash tills. It is also used as a secondary application in DOSBox to enable emulation of Win16 games on 64-bit Windows.
On July 9, 2008, it was announced that Windows for Workgroups 3.11 for the embedded devices channel would no longer be made available for OEM distribution as of November 1, 2008.
On July 14, 2013, Linux 3.11 was officially named "Linux For Workgroups" as a tongue-in-cheek reference to "Windows for Workgroups 3.11".