Start Define validating parser

Define validating parser

The Extensible Markup Language (XML) is descriptively identified in the XML 1.0 W3C Recommendation as "an extremely simple dialect [or 'subset'] of SGML" the goal of which "is to enable generic SGML to be served, received, and processed on the Web in the way that is now possible with HTML," for which reason "XML has been designed for ease of implementation, and for interoperability with both SGML and HTML." Note that the "HTML" referenced in the preceding sentence (bis) means HTML 4.0 and 3.2 which were in common use as of 10-February-1998, when the XML 1.0 specification was published as a W3C Recommendation.

HTML is composed of a tree of HTML nodes, such as text nodes. Nodes can also have content, including other nodes and text. For example, the Presentation by the web browser, such as screen rendering or access by Java Script, is then performed on this internal model, not the original document.

Early HTML documents, and to a lesser extent today, were largely invalid HTML and riddled with syntax errors.

The specifications are now maintained by the W3C XML Core Working Group.

These working groups were designed to have close liaison relationships with the W3C's Extensible Style[sheet] Language (XSL) Working Group and Document Object Model (DOM) Working Group.

W3C Members can also participate in the W3C XML Schema Interest Group, a forum for the discussion of technical issues relating to the development of XML Schema.

See also: Robin Cover's index of XML Schema materials.

You use a Regular Expression to find strings that match a specific pattern.