After the XML declaration, the document prolog can include a DTD, which lets you specify the kinds of tags that can be included in your XML document. In addition to telling a validating parser which tags are valid, and in what arrangements, a DTD tells both validating and nonvalidating parsers where text is expected, which lets the parser determine whether the whitespace it sees is significant or ignorable.

This is the generic document which describes a HTML or XHTML document. In short, it defines what is presentation and what is content of information in a given document, a little like the classic distinction between form and content.

This report documents the design of the XML specification DTD. This release of the report corresponds to the DTD with the FPI "-//W3C//DTD Specification Version 2.0//EN".

DTD to XML Schema translator lets you translate a Document Type Definition into an XML Schema (REC-xmlschema-1-20010502). The translator can map meaningful DTD entities onto XML Schema constructs (simpleType, attributeGroup, group); the XML document model is not anonymized. In addition, the translator can map DTD comments onto XML Schema documentation nodes in various ways.

The DTD Parser is a set of Java packages for exploring DTDs. For example, it could be used by software that generates a database schema or Java classes from a DTD.

As I indicated a couple of days ago I mentioned that the CApH group has been working on the problem of describing the semantics of elements.

This introductory article shows how to create XML Document Type Definitions (DTDs) and well-formed, well-defined XML files that can be validated by the XML parser of your choice. While you don't have to include a DTD with every XML file you produce, doing so will make your life a lot easier. Not only will a DTD enforce the syntax you've established for your XML files, it will also allow your files to be parsed by a validating XML parser. Code samples include DTD and XML document examples.

The arrival of any new schema language usually brings a utility to convert DTDs to that language, but using such a utility on a large collection of sophisticated DTDs isn't enough to provide a smooth transition for a big publishing organization. Even if all the DTD developers are trained in the new schema language beforehand, a sudden change in their responsibilities to maintaining their large, complex schemas in the new syntax is impractical.

This section uses the Echo program to see what happens when you reference xhtml.dtd in slideshow.dtd. It also covers the kinds of warnings that are generated by the SAX parser when a DTD is present.

The DTD you've defined so far is fine for use with the nonvalidating parser. It tells where text is expected and where it isn't, which is all the nonvalidating parser is going to pay attention to. But for use with the validating parser, the DTD needs to specify the valid attributes for the different elements. You'll do that in this section, after which you'll define one internal entity and one external entity that you can reference in your XML file.

The following DTD version of the specification is provided to communicate the basic design of the structural layer. See the following paper for more detailed explanations:

<!-- This DTD fragment is identified by and should be available at <a href="http://www.w3.org/Metadata/RDF/Group/9710/rdf.dtd">http://www.w3.org/Metadata/RDF ...

<!-- =
This is the DTD for SVG 1.0. The specification for SVG ...

The primary purpose of defining XHTML modules and a general modularization methodology is to ease the development of document types that are based upon XHTML. These document types may extend XHTML by integrating additional capabilities (e.g. [SMIL] or [MathML]), or they may define a subset of XHTML for use in a specialized device. Regardless of the application, XHTML modules are up to the task. This section describes the techniques that document type designers must use in order to take advantage of this modularization architecture.

A DTD is one component inside an SGML or XML environment. It defines the syntactic rules according to which a document can be composed. There are no semantics associated with the elements and attributes defined in a DTD, although normally the names chosen for elements and attributes will have some meaning to them.

The XML "Document Type Definition" (DTD) for HDF5 is the standard DTD to describe HDF5 files and their contents. This DTD should be used by all applications that describe HDF5 files with XML.

Top 15 reasons for avoiding DTD.

The <!DOCTYPE> declaration is the very first thing in your document, before the <html> tag. This tag tells the browser which HTML or XHTML specification the document uses.

dtddoc is a DTD documentation generator which can read a DTD and associated documentation written in XML and generate nicely formatted HTML documentation or, experimentally, DocBook RefEntry documentation. Later and more complete releases may provide features for supporting other formats as well.

The TEI DTD has found wide acceptance in the academic world for marking up texts and documents, and you are encouraged to use it as an alternative to the Gutenberg DTD's. Although the initial 'learning curve' is quite steep, it becomes much easier as one goes along.