GNU Emacs Manual. Node: Key Bindings
28.4: Customizing Key Bindings
This section describes key bindings, which map keys to commands,
and keymaps, which record key bindings. It also explains how
to customize key bindings.
Recall that a command is a Lisp function whose definition provides for
interactive use. Like every Lisp function, a command has a function
name which usually consists of lower-case letters and hyphens.