Microsoft launched Windows 1.0 in 1985 as its first retail version of Windows.
Windows 1.0 was released on November 20, 1985. It provided a graphical environment that ran on top of MS-DOS and included early versions of programs such as Paint, Write, Notepad, and Calculator. The system used tiled windows rather than the overlapping windows familiar from later releases.
Microsoft had announced Windows in 1983, but development and release took several years. Windows 1.0 required MS-DOS and was designed for IBM PC-compatible computers. It was not a fully independent operating system in the modern sense.
Windows 95 became much more influential because it introduced a widely recognized Start menu and taskbar, but it was not the first Windows release. Windows 1.0 established the product line that eventually became Microsoft’s dominant desktop platform.