To kind of explain what Linux is, you have to explain what an operating system is. And the thing about an operating system is that you're never ever supposed to see it. Because nobody really uses an operating system; people use programs on their computer. And the only mission in life of an operating system is to help those programs run. So an operating system never does anything on its own; it's only waiting for the programs to ask for certain resources, or ask for a certain file on the disk, or ask to connect to the outside world. And then the operating system steps in and tries to make it easy for people to write programs.

Interview in Revolution OS, documentary, 2001. - 2000-04