+This is the reference distribution for the Xigxag string-copying automaton.
+For a definition of the Xigxag automaton, see the file `xigxag.html` in
+the `doc` directory. (I didn't convert it from HTML to Markdown because
+it has a lot of mathematical-type markup, like subscripts and superscripts,
+that don't have equivalents in core Markdown, and the main advantage of it
+being in Markdown is so that it can be viewed directly on Github and
+Bitbucket. It should probably be converted to some more mathematically-
+oriented markup language at some point, I suppose.)
+This distribution also contains an "interpreter" for Xigxag, written in
+Perl, as `xigxag.pl` in the `src` directory.
+All of these materials are in the public domain; see the file UNLICENSE
+in the distribution's root directory for more information.