The final stage of the boot process starts one or more programs that allow you to log in to the system console. Linux has two primary display modes: console (text) mode, and an X Window System server (graphics mode, usually via a display manager). The kernel boots in console mode, but on most distributions the system switches over to graphics mode near when the rc*.d commands complete.
Linux has several virtual consoles. Each virtual console may run in graphics or text mode. When in text mode, you can switch between consoles with an ALT-Function key combination — for example, ALT-F1 takes you to /dev/tty1, ALT-F2 goes to /dev/tty2, and so on.
A virtual console used by XFree86 in graphics mode is slightly different. Rather than getting a virtual console assignment directly from /etc/inittab, an XFree86 server takes over a free virtual console. For example, if you have getty processes running on tty1 and tty2, a new XFree86 server takes over tty3. In addition, after XFree86 puts a virtual console into graphics mode, you must normally press a CONTROL-ALT-Function key combination to switch to another virtual console instead of the simpler ALT-Function key combination.
The upshot of all of this is that if you want to see your text console after your system boots, press CONTROL-ALT-F1. To get back to the X11 session, press ALT-F2, ALT-F3, and so on, until you get to the X session.