You may have previously used the W3C validator to validate your HTML; however, you may not be aware that it has been updated to have experimental support for the draft specification of HTML5.To validate your HTML, visit the W3C validator ( validator.w3.org ) and either validate by entering the direct URL of your site or paste the HTML of your site into the text area provided. Validation of HTML can be used: 1. As a debugging tool: The simplest bug to fix in HTML are those caused by writing invalid code. A simple validation should highlight problems with your HTML, which you can promptly fix. 2. To maintain quality of code: By ensuring code always passes the W3C validation , it maintains a level of quality in the code. 3. Ensuring ease of maintenance: Although invalid code may not break your site in the short term, unexpected bugs can crop up when you later amend that code, and validating helps minimize this.