RISC OS
More info
- Creator
- Acorn Computers
- Released
- 1987 (as Arthur), 1989 (RISC OS 2)
- Type
- Operating system with desktop
- License
- Apache 2.0 (since 2018)
- Website
- riscosopen.org
Acorn's operating system for the Archimedes, whose desktop in 1989 had an icon bar, anti-aliased fonts and drag-and-drop saving, years before the big players had anything similar.
The first version was called Arthur and shipped with the Archimedes in 1987 as a stopgap while something better was written. The something better was RISC OS 2 in April 1989, a WIMP desktop with several quirks that turned out to last. Along the bottom ran the icon bar, devices on the left and applications on the right, much like Windows 95's taskbar six years later. There was no menu bar at all: every menu hung off the middle mouse button, and the three buttons were called Select, Menu and Adjust. You saved by dragging the file's icon from the save dialog into a directory window, or straight into another application. File types were metadata rather than extensions, applications were directories with an exclamation mark in front, and fonts were drawn anti-aliased everywhere on screen, which no other desktop did in 1989.
Underneath it was simpler: cooperative multitasking, in which a program must call Wimp_Poll to give up the processor, and next to no memory protection between tasks. Acorn gave up on computers in 1998 and the system took a winding path through RISCOS Ltd and Castle Technology before RISC OS Open received the code in 2006 and released it under the Apache license in 2018. Since 2012 it has run on the Raspberry Pi, where a band of enthusiasts keeps using a desktop that is essentially the 1989 one, only faster than it ever was.