XHTML DTD
In a XHTML document, the XHTML code need to respect to all of the grammar, rules, and syntax in the XHTML DTD. Specificall, it is necessary to have the DOCTYPE tag in that code in order to declare the DTD (Document Type Definition). The purpose of the !DOCTYPE tag is to inform browsers and HTML validators what type of document is.
The XHTML standard defines three Document Type Definitions: Frameset, Strict, and Transitional. One thing that you keep in mind is that the most common is the XHTML Transitional.
-Frameset
First, when you have two or more frames in the HTML document (regardless Cascading Style Sheets), this type would be suitable for your page.This is the syntax of Frameset declaration :
| <!DOCTYPE html PUBLIC "-//W3C//DTD XHTML 1.0 Frameset//EN" "http://www.w3.org/TR/xhtml1/DTD/xhtml1-frameset.dtd"> |
-Strict
Second, when you use Cascading Style Sheets (CSS) to manage the appearance of a HTML document. It is recommend to use this type of DTD only if you are certain that your viewer has a modern browser that is able to interpret CSS.This is the syntax of Strict declaration :
| <!DOCTYPE html PUBLIC "-//W3C//DTD XHTML 1.0 Strict//EN" "http://www.w3.org/TR/xhtml1/DTD/xhtml1-strict.dtd"> |
-Transitional
Last but not least, when you use HTML to create a web page appearance. This type of DTD would guarantee that audience can see your XHTML document correctly because this DTD type can apply to the browsers that don't support Cascading Style Sheets.This is the syntax of Transitional declaration :
| <!DOCTYPE html PUBLIC "-//W3C//DTD XHTML 1.0 Transitional//EN" "http://www.w3.org/TR/xhtml1/DTD/xhtml1-transitional.dtd"> > |
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This tutorial is final project for INFSCI 2000, Fall 2004
Copyright 2004 School of Information Science, University of Pittsburgh