 By
migrating to XHTML today, content developers can enter the XML world with all
of its attendant benefits, while still remaining confident in their
content's backward and future compatibility.</p>

<h2><a name="html4" id="html4">1.1 What is HTML 4.0?</a></h2>

<p>HTML 4.0 <a href="#ref-html4">[HTML]</a> is an <abbr title="Standard
Generalized Markup Language">SGML</abbr> (Standard
Generalized Markup Language) application conforming to
International Standard <abbr title="Organization for International
Stan