Evolution of (X)HTML

From a static, monolithic SGML document type
to a dynamic, modular and extensible family of XML modules

Inflating HTML

More features: HTML 2.0, HTML+, HTML 3.0, HTML 3.2, HTML 4.01

Form controls, complex tables, equations, frames, etc.

Separating Style

Work on CSS started in 1994 to separate style from structure

CSS is extended to XML

Moving to XML

XHTML 1.0: HTML 4.01 in XML, three "flavors" (strict, transitional, frameset)

XHTML 1.1: Modularization, same features

XHTML 2.0: not intended to be backward compatible