See how the world's most popular operating system has evolved over the last quarter century
1985: Windows 1.0
When Windows 1.0 was released, it made a ripple, not a splash. It had to be run on top of DOS, few applications were written for it, and application windows couldn't be overlapped (they had to be tiled). Still, the OS allowed for multitasking of Windows apps (not DOS ones) and, even though few knew it at the time, it would eventually become the foundation for the Microsoft empire. Windows 1.0 shipped with a handful of apps, including the Notepad text editor, a rudimentary calendar and the long-lived graphics painting program Paint. The operating system required MS-DOS Version 2.0, 256KB of memory and a graphics adapter. It could be run either from a hard disk or on two floppy disks running simultaneously -- in other words, you couldn't swap the disks in and out of a single drive.