In the world of search engine optimization, a perennial argument is whether Google’s ranking factors look for clean code in a Web site. The W3C has developed two popular tools that check Web sites for errors: The W3C validation tool looks at HTML code, while the CSS validation tool checks the CSS Style Sheet. These free tools scan all of a site’s code to make sure it is compliant with current Web standards. Not long ago, Matt Cutts, a Google software engineer, said — not for the first time — that W3C Validation does not affect search engine rankings.
