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.