Windows 1.0: Where it begins
Release date: Nov. 20, 1985
An outgrowth of MS-DOS, Microsoft announced Windows in 1983 and finally released it on Nov. 20, 1985. (See related story.) System requirements for the 16-bit Windows 1.0 included MS-DOS version 2.0, two double-sided disk drives or a hard disk, a graphics-adapter card, and at least 256K of memory. Although this first version was a little-used alternative to Apple's Macintosh, Microsoft actually continued to offer support for Windows 1.0 until Dec. 31, 2001, a few months after the release of Windows XP.