Microsoft shipped the first version of Windows

On November 20, 1985, Microsoft released Windows 1.0, a graphical operating environment layered on top of MS-DOS. Instead of typing commands at a blinking prompt, users could click through drop-down menus, scroll bars, and tiled windows with a mouse.

The launch was famously overdue. Microsoft had announced Windows back in November 1983 and promised it within months, but technical fights, including a debate over tiled versus overlapping windows, dragged the project out and earned it accusations of being “vaporware.” By the company’s own count, the first version took some 110,000 programming hours.

Windows 1.0 was widely judged a flop, yet it seeded the most-used desktop platform on Earth.

Priced at $99, version 1.0 bundled a Calculator, Notepad, and Paint, but reviewers found it slow and underwhelming, and few copies sold. Microsoft’s real breakthrough waited until Windows 3.0 in 1990. Still, this clunky debut launched a product line that would dominate personal computing.