Original: Typically daemons have names that end with the letter "d": for example, syslogd, the daemon that handles the system log, or sshd, which handles incoming SSH connections.
Simplified: Normally, daemons have names that end with the letter "d": for example, syslogd, the daemon that handles the system log, httpd, a daemon that handles web requests or sshd, which takes care of incoming SSH connections.