Windows 1.0 was Microsoft’s first retail Windows operating system, launched in 1985.
Microsoft introduced Windows 1.0 on November 20, 1985. It provided a graphical environment that ran on top of MS-DOS, allowing users to work with windows, menus, icons, and a mouse rather than relying only on typed commands.
The release included early versions of applications such as Calculator, Paint, Notepad, and a clock. Windows 1.0 was not a complete replacement for DOS; it was a graphical operating environment that depended on it.
Some readers confuse the first Windows release with Windows 3.0 or Windows 95, which were far more commercially influential. Windows 3.0 arrived in 1990, while Windows 95 introduced the Start menu and taskbar in 1995.