In reply to this criticism one is normally reminded that Unix was invented for a PDP7, which had about as much memory as an earthworm and CPU power to match. That is, the user interface was designed to minimize the time required to decode a command. That meant short, fixed-case, commands, and no minimum matching. But 1969 is a long time ago, and both memory and speed have improved a thousandfold since then. — A Requiem for a Dying Operating System
Still, I like short command names like rm or ls.