Google, Bing and Yahoo today launched a new initiative that will introduce a common vocabulary for adding additional markup and structured data to websites and – by extension – search engine listings. Schema.org, as this new markup is called, allows website owners to give search engines better ways to understand the content on their sites. With schema.org, you can, for example, ensure that a search engine knows that something on your site is a recipe, a movie review with a rating, a listing for a local business or that a specific page is about a product. In total, the schema.org hierarchy knows of a few hundred different content types that can be described through its vocabulary.
Until now, every search engine offered its own way of doing something like this. Google had its Rich Snippets, for example, while Yahoo had SearchMonkey. It’s also worth noting that there have long been formats like RDF and microformats that allowed website owners to offer structured data to search engines. Most search engines already understand this data, but as Microsoft points out in its announcement, the company feels “strongly that by partnering with Google and Yahoo! on standard schemas webmasters can be more efficient with the time they invest.” That doesn’t quite explain why these three companies didn’t decide to work with one of the existing standards, though.