Useful Highlighting
-------------------
Highlighting Commands are Useful
--------------------------------

The highlighting commands can be used to extract useful information
from the file, such as lists of functions or file names.  It is
possible, for example, to write a program in Emacs Lisp (or a keyboard
macro) to insert an index entry after every paragraph that contains
words or phrases marked by a specified command.  You could do this to
construct an index of functions if you had not already made the
entries.

The commands serve a variety of purposes:

@code{sample-code}
Indicate text that is a literal example of a piece of a program.

@kbd{keyboard-characters}
Indicate keyboard input.

@key{key-name}
Indicate the conventional name for a key on a keyboard.

@samp{text}
Indicate text that is a literal example of a sequence of characters.

@var{metasyntactic-variable}
Indicate a metasyntactic variable.

@env{environment-variable}
Indicate an environment variable.

@file{file-name}
Indicate the name of a file.

@command{command-name}
Indicate the name of a command.

@option{option}
Indicate a command-line option.

@dfn{term}
Indicate the introductory or defining use of a term.

@cite{reference}
Indicate the name of a book.

@acronym{acronym}
Indicate an acronym.

@url{uniform-resource-locator}
Indicate a uniform resource locator for the World Wide Web.

@email{email-address[, displayed-text]}
Indicate an electronic mail address.



