The keyboard is our main user interface. So just a word about entering commands: Remember, to direct keyboard entries to a window, you must click on the terminal window before typing into it, unless you have enabled the “Auto Raise” feature. You begin by typing on a line. To complete a command, you must hit the Enter key. Once you hit Enter, the command is issued. Before that, you can edit it. If you make a mistake, use the backspace key to rub out the previous character(s), or use Ctrl-u to erase the entire line. Ctrl-u means holding down the Ctrl key while hitting the u key. Try this a few times with the pwd command.