Google, Microsoft, and Yahoo Team Up to Advance Semantic Web
Google, Microsoft, and Yahoo have teamed up to encourage Web page operators to make the meaning of their pages understandable to search engines.
The three big Web companies launched the semantic-Web-technology initiative, known as Schema.org, last week. It defines an interconnected vocabulary of terms that can be added to the HTML markup of a Web page to communicate the meaning of concepts on the page. This data will allow search engines to better understand how useful a page may be for a given search query.
Schema.org asks for semantic markup to be written using a format known as microdata, which is not yet a W3C standard, rather than RDFa, a more widely used W3C-approved alternative.