W3C VALIDATION

W3C basically it stand World Wide Web Consortium allows users to check HTML documents for conformance to HTML (hyper text markup language) or XHTML. It also provides a quick method for web page authors to check their posted pages for mark-up errors.

Most Web documents are written using markup languages, such as HTML or XHTML. These languages are defined by technical specifications, which usually include a machine-readable formal grammar (and vocabulary). The act of checking a document against these constraints is called validation, and this is what the Markup Validator does.

W3C home page for the XHTML2 Working group, which was chartered in March 2007. XHTML2 Working group is to fulfill the promise of XML for applying XHTML to a wide variety of platforms with proper attention paid to internationalization, accessibility, a device –independence, usability and document structuring. The group will provide an essential piece for supporting rich Web content that combines XHTML with other W3C work on areas such as math, scalable vector graphic, synchronized multimedia, and forms, in cooperation with other Working Groups.

W3C produces what are known as “Recommendations”. These are specifications, developed by W3C working groups, and then reviewed by Members of the Consortium. A W3C Recommendation indicates that consensus has been reached among the Consortium Members that a specification is appropriate for widespread use.
There are also many excellent tools developed outside W3C to help improve the quality of Web pages.

HTML tidy, originally developed at W3C, is a program that can help automatically clean up HTML pages.
Validome offer a very reliable validator for HTML, XHTML and WML, in different languages.
The WDG HTML validator is another excellent online validation service.
Site Valet by Nick Kew is a comprehensive set of Quality Assurance tools for checking and monitoring your web sites.

The W3C also hosts a number of other Open Source software projects. In addition to this validator, the W3C is offering a number of other tools to help you check other types of documents (CSS, RDF, P3P…), find broken links in your Web pages, and so on.

Validation Web documents is an important step which dramatically help improving and ensuring their quality, and it can save a lot of time and money (read more on why validating matters). Validation is, however, neither a full quality check, nor is it strictly equivalent to checking for conformance to the specification.

This validator can process documents written in most markup languages. Supported documents types include the HTML (through HTML 4.01) and XHTML (1.0 and 1.1) family. The Markup Validator can also validate web documents written with an SGML or XML DTD, provided they use a proper document type declaration.

This validator is also “An HTML validating system conforming to International Standard ISO/IEC 15445—Hypertext Markup Language, and International Standard ISO 8879—Standard Generalized Markup Language (SGML)” – which basically means that in addition to W3C recommendations, it can validated according to these ISO standard.