input syntax, and as internal mechanism to glue together modules of
the program. This section is a very brief overview of entering data in
Scheme.@footnote{If you want to know more about Scheme, see
-@uref{http://www.schemers.org}.}
+@uref{http://@/www@/.schemers@/.org}.}
The most basic thing of a language is data: numbers, character
strings, lists, etc. Here is a list of data types that are relevant to