Here is a summary of help commands for accessing the built-in documentation. Most of these are described in more detail in the following sections.

C-h a topics RET

Display a list of commands whose names match topics (apropos-command). Apropos.

C-h b

Display all active key bindings; minor mode bindings first, then those of the major mode, then global bindings (describe-bindings). Misc Help.

C-h C-q

Toggle display of a window showing popular commands and their key bindings. Misc Help.

C-h c key

Show the name of the command that the key sequence key is bound to (describe-key-briefly). Here c stands for ``character''. For more extensive information on key, use C-h k. Key Help.

C-h d topics RET

Display the commands and variables whose documentation matches topics (apropos-documentation). Apropos.

C-h e

Display the *Messages* buffer (view-echo-area-messages). Misc Help.

C-h f function RET

Display documentation on the Lisp function named function (describe-function). Since commands are Lisp functions, this works for commands too, but you can also use C-h x. Name Help.

C-h h

Display the HELLO file, which shows examples of various character sets.

C-h i

Run Info, the GNU documentation browser (info). The Emacs manual is available in Info. Misc Help.

C-h k key

Display the name and documentation of the command that key runs (describe-key). Key Help.

C-h l

Display a description of your last 300 keystrokes (view-lossage). Misc Help.

C-h m

Display documentation of the current major mode and minor modes (describe-mode). Misc Help.

C-h n

Display news of recent Emacs changes (view-emacs-news). Help Files.

C-h o symbol

Display documentation of the Lisp symbol named symbol (describe-symbol). This will show the documentation of all kinds of symbols: functions, variables, and faces. Name Help.

C-h p

Find packages by topic keyword (finder-by-keyword). Package Keywords. This lists packages using a package menu buffer. Packages.

C-h P package RET

Display documentation about the specified package (describe-package). Package Keywords.

C-h r

Display the Emacs manual in Info (info-emacs-manual).

C-h s

Display the contents of the current syntax table (describe-syntax). Misc Help. The syntax table says which characters are opening delimiters, which are parts of words, and so on. Syntax Tables, for details.

C-h t

Enter the Emacs interactive tutorial (help-with-tutorial).

C-h v var RET

Display the documentation of the Lisp variable var (describe-variable). Name Help.

C-h w command RET

Show which keys run the command named command (where-is). Key Help.

C-h x command RET

Display documentation on the named command (describe-command). Name Help.

C-h C coding RET

Describe the coding system coding (describe-coding-system). Coding Systems.

C-h C RET

Describe the coding systems currently in use.

C-h F command RET

Enter Info and go to the node that documents the Emacs command command (Info-goto-emacs-command-node). Name Help.

C-h I method RET

Describe the input method method (describe-input-method). Select Input Method.

C-h K key

Enter Info and go to the node that documents the key sequence key (Info-goto-emacs-key-command-node). Key Help.

C-h L language-env RET

Display information on the character sets, coding systems, and input methods used in language environment language-env (describe-language-environment). Language Environments.

C-h S symbol RET

Display the Info documentation on symbol symbol according to the programming language you are editing (info-lookup-symbol). Misc Help.

C-h .

Display the help message for a special text area, if point is in one (display-local-help). (These include, for example, links in *Help* buffers.) Help Echo. If you invoke this command with a prefix argument, C-u C-h ., and point is on a button or a widget, this command will pop a new buffer that describes that button/widget.