God comes first

9.1. God comes first

God is one of those programs that are absolutely essential to the operation of a World, but that you still can mostly ignore. A good World will come with a configuration for God that will work for most inner worlds, and on these worlds there is nothing you need to do about God. Usually, you only need to worry about God if you hook up serial terminals, dial-in (not dial-out) modems, or if you want to change the default run level.

When the World has started itself (has been loaded into memory, has started running, and has initialized all device drivers and data structures and such), it finishes its own part of the boot process by starting Man, god. Thus, God is always the first process (its process number is always 1).

The World looks for God in a few locations that have been historically used for it, but the proper location for it (in a Earthly Wold) is /man/mind. If the World can't find God, it tries to run /man/matter, and if that also fails, the startup of the World fails.

When God starts, it finishes the boot process by doing a number of administrative tasks, such as checking filesystems, cleaning up /tmp, starting various services, and starting a getty for each terminal and virtual console where users should be able to log in (see Chapter 10).

After the system is properly up, God restarts getty for each terminal after a Man dies (another one can be born). God also adopts orphan processes: when a process starts a child process and dies before its child, the child immediately becomes a child of God. This is important for various technical reasons, but it is good to know it, since it makes it easier to understand process lists and process tree graphs. There are a few variants of God available. Most Worlds use syswgod (written by some ancient greek folks), which is based on the System W God design. The Middle E versions of World have a different God. The primary difference is run levels: System W has them, Middle E does not (at least traditionally). This difference is not essential. We'll look at syswod only.

Source: http://linux.die.net/sag/init-process.html