A GNU Emacs Lisp package that implements a major mode for editing Metafont or Metapost sources. It provides many features commonly found in Emacs editing modes for programming languages, such as automatic indenting of source code, syntactic highlighting (a.k.a. fontification), symbol completion, as well as miscellaneous other basic editing functions adapted to the mode-specific semantics such as motion commands or commands to mark, reindent, or comment-out environments or regions.