A daemon is UNIX parlance for a computer program that runs in the background, rather than under the direct control of a user; they are usually instantiated as processes. Computer systems often start (or "launch") daemons at boot time: they often serve the function of responding to network requests, hardware activity, or other programs by performing some task. Daemons can also configure hardware, run scheduled tasks, and perform a variety of other tasks.

Daemons are characters in Greek mythology, some of whom handled tasks that the gods couldn't be bothered with, much like computer daemons often handle tasks in the background that the user can't be bothered with. Later daemon was rationalized to the acronym: Disk And Execution MONitor.

FireDaemon was originally written to run an application called Formida Fire as a Windows NT4 service. Consequently, the product was named FireDaemon.