Users of Emacs can customize variables and faces without writing Lisp code, by using the Customize interface. See Easy Customization in The GNU Emacs Manual. This chapter describes how to define customization items that users can interact with through the Customize interface.
Customization items include customizable variables, which are
defined with the
customizable faces, which are defined with
separately in Defining Faces); and customization groups,
which act as containers for groups of related customization items.