Linux is a multiuser and multitasking system. The advantages of these features can be appreciated even on a stand-alone PC system. In text mode, there are six virtual consoles available. Switch between them using Alt+F1 to Alt+F6. The seventh console is reserved for X and the tenth console shows kernel messages. More or fewer consoles can be assigned by modifying the file /etc/inittab.
To switch to a console from X without shutting it down, use Ctrl+Alt+F1 to Ctrl+Alt+F6. To return to X, press Alt+F7.