An operating system designed at MIT as a successor to the CTSS system
Homepage: http://www.multicians.org/multics.html Wikipedia: http://en.wikipedia.org/wiki/Multics Source Code: http://web.mit.edu/multics-history/#community License: Open source
The developers of Unix worked on Multics, and Unix took various concepts from it. The old joke was "Unix is Multics without the balls"