Emacs calls these function keys. Emacs usually writes their names with surrounding
> when it interacts with you.
See the Emacs manual, nodes Function Keys, Keymaps and User Input.
For example (from Emacs manual, node Keymaps):
Most modern keyboards have function keys as well as character keys.
Function keys send input events just as character keys do, and keymaps
can have bindings for them. Key sequences can mix function keys and
characters. For example, if your keyboard has a
<Home> function key,
Emacs can recognize key sequences like
C-x <Home>. You can even mix
mouse events with keyboard events, such as
And (from Emacs manual, node Function Keys):
Key sequences can contain function keys as well as ordinary characters.
Just as Lisp characters (actually integers) represent keyboard
characters, Lisp symbols represent function keys. If the function key
has a word as its label, then that word is also the name of the
corresponding Lisp symbol. Here are the conventional Lisp names for
common function keys:
down -- Cursor arrow keys.
And the Glossary node of the manual has this entry:
Function Key -- A function key is a key on the keyboard that sends input but does not correspond to any character.
See also the Elisp manual, node Function Keys.
Emacs also has fake function keys, which it uses to represent menu names, menu items, and tool-bar items. See the Elisp manual, nodes Menu Example and Tool Bar for information about these:
These symbols are treated as function keys, but they are not real
function keys on the keyboard. They do not affect the functioning of
the menu itself, but they are echoed in the echo area when the user
selects from the menu, and they appear in the output of
As @phils has mentioned, Emacs can't know what function keys your keyboard and system might support, but you can use
C-h c or
C-h k to try various keyboard keys and see (1) whether Emacs recognizes them (instead of them being captured by your OS or some other app) and (2) what Emacs calls them (e.g. whether it calls them
As for how to learn about function keys using Emacs help:
See above, for help using the manuals. As always,
i in Info is your friend, and you can also search using
C-M-s function key.
M-x apropos function key gives you quick info (and links) about commands, other functions, and variables whose names contain those words. And
M-x apropos documentation function key gives you such info about such things whose documentation mentions those words.