About rich snippets and structured data - Webmaster Tools Help
Rich snippets (microdata, microformats, RDFa, and Data Highlighter) Snippets—the few lines of text that appear under every search result—are designed to give users a sense for what’s on the page and why it’s relevant to their query. If Google understands the content on your pages, we can create rich snippets—detailed information intended to help users with specific queries. For example, the snippet for a restaurant might show the average review and price range; the snippet for a recipe page might show the total preparation time, a photo, and the recipe’s review rating; and the snippet for a music album could list songs along with a link to play each song. These rich snippets help users recognize when your site is relevant to their search, and may result in more clicks to your pages. Three steps to rich snippets: 1. Google suggests using microdata, but any of the three formats below are acceptable. 2. Google supports rich snippets for these content types: 3. That’s it! Use HTML markup if...
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