dragon

n. [MIT] A program similar to a daemon, except that it is not invoked at all, but is instead used by the system to perform various secondary tasks. A typical example would be an accounting program, which keeps track of who is logged in, accumulates load-average statistics, etc. Under ITS, many terminals displayed a list of people logged in, where they were, what they were running, etc., along with some random picture (such as a unicorn, Snoopy, or the Enterprise), which was generated by the `name dragon'. Usage rare outside MIT --- under UNIX and most other OSes this would be called a `background demon' or daemon. The best-known UNIX example of a dragon is `cron(1)'. At SAIL, they called this sort of thing a `phantom'.