4. (popup menus and menubars). If there is a string of words at the top of the screen ("menubar"), touch one of the words with the pointer using the mouse and then hold down the mouse button. A menu should pop up. If you continue holding down the mouse button and drag down the menu, then let go, you will select one of the commands. If you don't want to activate a command, drag the pointer away from the commands (towards the middle of the screen, say) and let go.
5. (getting the computer's attention) No luck? Try hitting "return" or "enter" a few times, look for keys labelled "break" or "escape", try "control-C" (hold down the key labelled "CTRL"—it works like the shift key on a typewriter—and then press "c", then let go of both keys).
6. (carriage return) Once the system is responding you usually have to hit the carriage return key (marked with a hooked arrow or "return" or "enter" or "CR" or "newline") or else click the mouse (left-most button if there are three) before anything permanent happens—like sending a command to the computer.
An exception is in "menu-driven" systems which print a list of options and expect you to type a number or letter (like "y" for yes, "n" for no). Sometimes answering a question with a carriage return gets you a default answer. The default is often indicated in brackets:
Do you really want to quit [n]?
Hitting return here will not quit.
7. (delete key) If you make a typing mistake, there is a key in the upper righthand corner labelled "del", "delete", "backspace", or with a backwards arrow or "x" on it that will erase what you typed.
8. (logging on) If you see a message like this:
Hello. Welcome to FUBAR system. Authorized persons only.
Username: xxx
Password: