... I will only talk about the ``System V'' style of init that Linux systems mostly use. ... Typically, the first thing it is told to do is to run an initialisation script. The program that executes (or interprets) this script is bash , the same program that gives you a command prompt. In Debian systems, the initialisation script is /etc/init.d/rcS , on Red Hat, /etc/rc.d/rc.sysinit . ... But S10syslog is really a link to /etc/init.d/syslog which is a script to start and stop the system logger. ...