This section describes the tt(yodl) program from the point of a meta-user, 
one who is interested in how macro files work, or one who wants to write a new 
converter. If you're just interested in using Yodl with the pre-existing 
converters and macro files, skip this chapter and continue with the macro 
package description (chapter ref(MACROPACKAGE)).

The YODL program the main converter of the Yodl package. The basic usage 
of the tt(yodl) program, tt(yodl)'s built-in macros, and the syntax of the
Yodl language is described here.
