So, we've seen that we've got at least two XML files, and numerous output files that must be produced. All output is produced by XSLT templates. Screenbook Maker is distributed with XSLT templates for all the output formats shown, and more. Each output format corresponds to one XSLT file.

Since Screenbook Maker users have access to the XSLT files, they can easily change the way an output format looks by editing the XSLT. For example, if you want to put a banner ad at the top of every HTML page in slide view, you simply edit the XSLT template that creates the slide version of the screenbook.

The only problem is, how is the average user to be able to figure out which of the many XSLT files to edit? And, since users may not know XSLT, how can the XSLT files be distributed and explained in such a way that the anyone who knows HTML will be able to edit the XSLT templates which produce HTML output?

There are basically only two possible solutions:

• Hire a team of programmers to create a fancy WYSYWIG editor that allows users to make some, but not all, of the changes they could make by editing the XSLT directly.
• Use Leo to distribute, categorize and explain the XSLT in such a clear fashion that any intelligent user who knows HTML will be able to edit the XSLT to produce any kind of HTML output that they want. More advanced users will be able to add completely new output formats.

Since at this point Screenbook Maker is a free program produced by a single programmer, option #1 is not realistic.