Switch to virtual terminal N (that is, switch to /dev/ttyN). If you have not created /dev/ttyN, it will be created when you use this command. There are keyboard shortcuts for this functionality as well. From a graphical desktop, you can press Ctrl-Alt-F1 through F12 to switch to different virtual terminals. In text mode, you can skip the Ctrl key and just use Alt-F1 through F12. To switch back to graphical mode, use Alt-F7.