+LilyPond uses the GNU Guile implementation of Scheme, which is
+based on the Scheme @qq{R5RS} standard. If you are learning Scheme
+to use with LilyPond, working with a different implementation (or
+referring to a different standard) is not recommended. Information
+on guile can be found at @uref{http://www.gnu.org/software/guile/}.
+The @qq{R5RS} Scheme standard is located at
+@uref{http://www.schemers.org/Documents/Standards/R5RS/}.
+
+The LilyPond installation also includes the Guile implementation of
+Scheme. On most systems you can experiment in a Scheme sandbox by
+opening a terminal window and typing @q{guile}. On some systems,
+notably Windows, you may need to set the environment variable
+@code{GUILE_LOAD_PATH} to the directory @code{../usr/shr/guile/1.8}
+in the LilyPond installation (for the full path to this directory
+see @ref{Other sources of information}). Alternatively, Windows
+users may simply chose @q{Run} from the Start menu and enter
+@q{guile}.
+
+The most basic concept in a language is data typing: numbers, character