You've probably gathered at this point that the init program is quite important on a Linux system. You can configure init by editing the file /etc/initttab, which is described in the inittab(5) man page. We'll just touch on one key line in this file:

# grep ^id: /etc/inittab
id:3:initdefault:

On my system, runlevel 3 is the default runlevel. It can be useful to change this value if you prefer your system to boot immediately into a graphical login (usually runlevel 4 or 5). To do so, simply edit the file and change the value on that line. But be careful! If you change it to something invalid, you'll probably have to employ the init=/bin/sh trick we mentioned earlier.