Terminology
The term was coined by the programmers of MIT's Project MAC. They took the name from Maxwell's demon, an imaginary being from a famous thought experiment that constantly works in the background, sorting molecules. Unix systems inherited this terminology. Daemons are also characters in Greek mythology, some of whom handled tasks that the gods could not be bothered with. BSD and some of its derivatives have adopted a daemon as its mascot, although this mascot is a variation of the demons that appear in Christian artwork.
The word daemon is an alternative spelling of demon, and is pronounced /ˈdiːmən/ DEE-mən. In the context of computer software, the original pronunciation /ˈdiːmən/ has drifted to /ˈdeɪmən/ DAY-mən for some speakers.
Alternate terms for daemon are service (Microsoft Windows NT), started task (IBM z/OS), server virtual machine (IBM VM), ghost job (XDS UTS).
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