+The template uses the syntax used by the [[!cpan HTML::Template]] perl
+module, which allows for some fairly complex things to be done. Consult its
+documentation for the full syntax, but all you really need to know are a
+few things:
+
+* Each parameter you pass to the template directive will generate a
+ template variable. There are also some pre-defined variables like PAGE
+ and BASENAME.
+* To insert the value of a variable, use `<TMPL_VAR variable>`. Wiki markup
+ in the value will first be converted to html.
+* To insert the raw value of a variable, with wiki markup not yet converted
+ to html, use `<TMPL_VAR raw_variable>`.