Introduction

The Markup Validation Service by the World Wide Web Consortium (W3C) allows Internet users to check HTML documents for conformance to HTML or XHTML standards. It also provides a quick method for web page authors to check their posted pages for mark-up errors.

References

1. http://en.wikipedia.org/wiki/W3C_Markup_Validation_Service
2. http://validator.w3.org
3. http://validator.w3.org/checklink
4. http://jigsaw.w3.org/css-validator/
5. http://www.anybrowser.com/
6. http://www.delorie.com/web/wpbcv.html