Yodl is not a word processor, not even an editor. At first glance you might
say, yeah, Yodl is just yet oneother document language.. why learn it?

First of all, Yodl may lower the threshold of new users to start writing
documents. An example of an excellent, though not very user-friendly document
language is LaTeX. Typing all the backslash and curly brace characters in
LaTeX and remembering that an asterisk must be typed as tt($*$) may be hard at
first. In such situations, a properly configured Yodl macro set removes these
obstacles and thereby helps novices. Yodl is designed to be easy to learn.
As the Yodl package is growing, so is the manual. The  ease of `learning Yodl' 
may thus somewhat diminish, but just keep in mind: as long as you need just 
plain texts, Yodl does OK. If you want more functionality, e.g., the 
composition of manual pages for Unix, dig into the documentation.

Second, Yodl permits to create more than one macro set, defining the same
commands, but leading to different output actions. Thereby, the same input 
file can be converted to several output formats, depending on the loaded macro 
set. In this, Yodl is a `general front' document language, which converts a 
Yodl document to a specialized language for further processing. This was of 
course one of my reasons to write Yodl: I needed a good converter for either 
LaTeX or HTML. 

Third, Yodl always allows an `escape route' to the output format. Most
situations can be handled with Yodl macros, but sure enough, some users will
want special actions for a given output format.  A typical example for the
necessity of such an escape route is the typesetting of mathematical formulas.
Say you want to use Yodl for a document that is converted either to LaTeX
(being a very good mathematical typesetter) or to HTML (a very poor
mathematical typesetter). An approach might be to decide em(inside the
document) how to typeset a mathematical formula. Yodl provides conditional
command processing to accomplish this. The decision would be based on the
output format: for LaTeX, you'd typeset the formula using all the facilities
that LaTeX offers, and for HTML you'd use poor-mans typesetting. Typically,
other pre-processors for documents don't allow such escape routes. Well, Yodl
does.
