Before going on, it’s important to be familiar with the typographical conventions used in this book.
When you should simultaneously hold down multiple keys, a notation like CTRL-a will be used. This means “press the Ctrl key and press lowercase letter a.” Some keyboards have both Alt and Meta; most home computers have only Alt, but the Alt key behaves like a Meta key. So if you have no Meta key, try the Alt key instead.
Keys like Alt and Meta are called modifier keys because they change the meaning of standard keys like the letter A. Sometimes you need to hold down more than one modifier; for example, Meta-Ctrl-a means to simultaneously press Meta, Ctrl, and lowercase a.
Some keys have a special notation – for example, Ret (Return/Enter), Del (Delete or sometimes Backspace), Esc (Escape). These should be fairly self-explanatory.
Spaces used instead of hyphens mean to press the keys in sequential order. For example, CTRL-a x RET means to simultaneously type Ctrl and lowercase a, followed by the letter x, followed by pressing Return. (On some keyboards, this key is labeled Enter. Same key, different name.)
In sample sessions, bold face text denotes characters typed by the user, italicized text denotes comments about a given part of the sample session, and all other text is output from entering a command. For shorter commands, you’ll sometimes find that the command can be found within other text, highlighed with a monospace font.