What is Structured Data, aka Rich Snippets or Schema.org?

What are Rich Snippets and why do we want them?

Rich Snippets is a fancy term for the ability of Google, Yahoo!, and eventually others to enhance and show more information on their search results.

Using Microdata markup or Schema tags on your published pages allows Google to better understand the data on your page. With markup, Google has the option of including Rich Snippets about your products in the search results. Search results stand out and give more information to the visitor when Rich Snippets are present. For an ecommerce site this information can include the description, price, stock status, product reviews and potentially an image (Yahoo! will show an image, Google doesn't currently display images).

These snippets come from the search engine's ability to get accurate data from your site. Currently engines will gather the data through Structured Data Markup (Schema.org markup - preferred, RDFa or Microdata). These different forms of markup add tags to your page so search engines can accurately pull data for your pricing, reviews, etc...

Google's information on their Structured Data rich snippets: http://www.google.com/support/webmasters/bin/answer.py?hl=en&answer=99170
Google's information on shopping site Structured Data rich snippets: http://googlewebmastercentral.blogspot.com/2010/11/rich-snippets-for-sho...