A major upgrade to Windows 3.0, introduced in 1992. It added more stability and support for multimedia, TrueType fonts, compound documents (OLE) and drag & drop. Windows 3.1 ran 16-bit Windows and DOS applications but was unable to run subsequent 32-bit Windows programs written for Windows 95 and beyond. Windows 3.11 added peer-to-peer networking and was the last 16-bit 3.x version of Windows.
After 32-bit Windows 95 was released, many 16-bit Windows 3.1 applications ran smoothly under Windows 95 and subsequent versions. However, the newer 32-bit versions of Windows supported long file names, and Windows 3.1 applications could not resolve them (see
Win Short file names). See
Windows 3.0 and
Windows 3.x modes.