TOPS-10

/tops-ten/ DEC's proprietary OS for the fabled PDP-10

machines, long a favourite of hackers but now effectively

extinct. A fountain of hacker folklore. See also ITS,

TOPS-20, TWENEX, VMS, operating system. TOPS-10 was

sometimes called BOTS-10 (from "bottoms-ten") as a comment on

the inappropriateness of describing it as the top of anything.

[Jargon File]