Emacs lisp programmers probably know the lisp-complete-symbol
command, usually bound to M-TAB. Users of the wonderful
ispell mode know and love the ispell-complete-word command from
that package. Similarly, AUC TeX has a TeX-complete-symbol
command, usually bound to C-c TAB. Using
LaTeX-complete-symbol makes it easier to type and remember the
names of long LaTeX macros.
In order to use TeX-complete-symbol, you should write a backslash
and the start of the macro. Typing C-c TAB will now complete as
much of the macro, as it unambiguously can. For example, if you type
``\renam'' and then `C-c TAB, it will expand to
``\renewcommand''.
Command: TeX-complete-symbol
(C-c TAB) Complete TeX symbol before point.
A more direct way to insert a macro is with TeX-insert-macro,
bound to C-c C-m. It has the advantage over completion that it
knows about the argument of most standard LaTeX macros, and will
prompt for them. It also knows about the type of the arguments, so it
will for example give completion for the argument to `\include'.
Some examples are listed below.
Command: TeX-insert-macro
(C-c C-m) Prompt (with completion) for the name of a TeX macro, and if AUC TeX knows the macro, prompt for each argument.
Completions works because AUC TeX can analyze TeX files, and store symbols in emacs lisp files for later retrieval. See section Automatic Customization, for more information.