As it turns out, there isn't much to the boot process:
1) A boot loader finds the kernel image on the disk, loads it into memory, and starts it.
2) The kernel initializes the devices and its drivers.
3) The kernel mounts the root filesystem.
4) The kernel starts a program called init.
5) init sets the rest of the processes in motion.
6) The last processes that init starts as part of the boot sequence allow you to log in.