Daemon

A daemon represents three things:

1. It is the process of daemonizing a program there is a C function for this called daemon(3).

2. A daemon is a program that runs a service on the system, it is not tied to a terminal and may only write reports to syslog or another logging mechanism. There is SMTP daemons such as sendmail that manage all mail operations, or the inetd superserver which manages a number of services such as chargen and ftp. A daemon orphans itself from the parent process and selects init (process 1) as its parent.

3. BSD's original mascot, looks like a devil and should not be confused with a demon (which is evil). The mascot has horns, holds a trident (or fork) in its hands and has a tail. It wears green sneakers (converse basketball sneakers probably) and is seen in early drawings as chasing a golden orb. FreeBSD uses this mascot extensively. OpenBSD has replaced the daemon mascot with puffy the blowfish. If you look closely on a picture of Puffy though the tail often looks like the silhouette of a daemon's head.