11 Help
Emacs provides extensive help features accessible through a single
character, C-h. C-h is a prefix key that is used for
commands that display documentation. The characters that you can type after
C-h are called help options. One help option is C-h;
that is how you ask for help about using C-h. To cancel, type
C-g. The function key <F1> is equivalent to C-h.
C-h C-h (help-for-help
) displays a list of the possible
help options, each with a brief description. Before you type a help
option, you can use <SPC> or <DEL> to scroll through the list.
C-h or <F1> means “help” in various other contexts as
well. After a prefix key, it displays a list of the alternatives that
can follow the prefix key. (A few prefix keys don't support
C-h, because they define other meanings for it, but they all
support <F1>.)
Most help buffers use a special major mode, Help mode, which lets you
scroll conveniently with <SPC> and <DEL>. It also offers
hyperlinks to URLs and further help regarding cross-referenced names, Info
nodes, customization buffers and the like. See Help Mode.
If you are looking for a certain feature, but don't know where
exactly it is documented, and aren't sure of the name of a
related command or variable, we recommend trying these methods. Usually
it is best to start with an apropos command, then try searching the
manual index, then finally look in the FAQ and the package keywords.
- C-h a topics <RET>
- This searches for commands whose names match topics, which
should be a keyword, a list of keywords, or a regular expression
(see Regexps). This command displays all the matches in a new
buffer. See Apropos.
- C-h i d m emacs <RET> i topic <RET>
- This looks up topic in the indices of the Emacs on-line manual.
If there are several matches, Emacs displays the first one. You can then
press , to move to other matches, until you find what you are
looking for.
- C-h i d m emacs <RET> s topic <RET>
- Similar, but searches for topic (which can be a regular
expression) in the text of the manual rather than in its
indices.
- C-h C-f
- This brings up the Emacs FAQ. You can use the Info commands
to browse it.
- C-h p
- Finally, you can try looking up a suitable package using keywords
pertinent to the feature you need. See Library Keywords.
To find the documentation of a key sequence or a menu item, type
C-h K and then type that key sequence or select the menu
item. This looks up the description of the command invoked by the key
or the menu in the appropriate manual (not necessarily the Emacs
manual). Likewise, use C-h F for reading documentation of a
command.