Actually, at least five...
> PDF - for those who care the most about presentation (Is
> anyone working on a forms POST interface for PDF?)
>
> SGML - for those who care about content markup and user
> editing
>
> HTML - the general purpose compromise that has features
> for both the presentation crowd and the markup crowd and
> satisfies neither.
(...and also provides a cross-platform user interface language)
Hyper-TeX - for sophisticated presentation of mathematically
intensive text and graphics.
VRML - for 3-dimensional hypermedia (and eventually, distributed
virtual reality).
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Paul Burchard <burchard@math.utah.edu>
``I'm still learning how to count backwards from infinity...''
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