HTML and CSS Reference
In-Depth Information
Appendix D. The HTML 4.01 DTD
The HTML 4.01 standard is formally defined as three Standard General-
ized Markup Language (SGML) Document Type Definitions (DTDs): the
Strict DTD, the Transitional DTD, and the Frameset DTD. The Strict DTD
defines only those elements that are not deprecated in the 4.0 stand-
ard. Ideally, everyone would create HTML documents that conform to the
Strict DTD. The Transitional DTD includes all those deprecated elements
and more accurately reflects the HTML in use today, with many older ele-
ments still in common use. The Frameset DTD is identical to the Trans-
itional DTD, with the exception that the document <body> is replaced by
the <frameset> tag.
Since the Transitional DTD provides the broadest coverage of all HTML
elements currently in use, it is the DTD upon which this topic is based
and the one we reproduce here. Note that we have reprinted this DTD
verbatim and have not attempted to add extensions to it. Where our de-
scription and the DTD deviate, assume the DTD is correct:
This is the HTML 4.01 Transitional DTD, which includes
presentation attributes and elements that W3C expects to phase out
as support for style sheets matures. Authors should use the Strict
DTD when possible, but may use the Transitional DTD when support
for presentation attributes and elements is required.
HTML 4 includes mechanisms for style sheets, scripting,
embedding objects, improved support for right to left and mixed
direction text, and enhancements to forms for improved
accessibility for people with disabilities.
Draft: $Date: 2006/10/25 17:08:45 $
Dave Raggett <>
Arnaud Le Hors <>
Ian Jacobs <>
Further information about HTML 4.01 is available at:
The HTML 4.01 specification includes additional
syntactic constraints that cannot be expressed within
Search WWH ::

Custom Search