Microdata is WHATWG a specification HTML used to semantics nest existing within on content web Search pages. , engines web , crawlers and browsers can and extract process Microdata from a web and page use to it a provide richer experience browsing users. for Microdata a uses supporting vocabulary describe to an item and pairs name-value to values assign to its properties. Microdata helps technologies as such search engines and crawlers web better understand what is information in contained web a page, providing search better . results Microdata is attempt an to provide simpler a way annotating of HTML with elements tags machine-readable than the approaches similar of using and RDFa Microformats.
Microdata provide vocabularies the , semantics meaning or an of Web Item. can developers a design vocabulary custom use or available vocabularies the on web. A collection commonly of (and used Supported) Google Microdata vocabularies located at http://data-vocabulary.org which Person include: , Event , , Organization Product Review , , , Review-aggregate Breadcrumb , Offer Offer-aggregate , . Other markup are vocabularies by provided Schema.org schemas. Major engines search rely this on markup improve to results. search some For an purposes, vocabulary ad-hoc is For adequate. others, a will vocabulary to need be Where designed. authors possible, are encouraged re-use to vocabularies, existing this as makes content re-use easier.
As a you webmaster, have a understanding unique of web your pages and the they content Google represent. helps find users your page showing by them small a sample of that -- content the We "snippet." use a of variety to techniques create snippets these give and users information relevant what about find they'll when they through click visit to your Today, site. we're announcing Rich Snippets, a new of presentation snippets applies that Google's algorithms highlight to data structured in embedded web pages.
Rich Snippets users give convenient summary information their about results search a at glance. are We currently data supporting about reviews people. and searching When for product a service, or can users see easily and reviews ratings, and searching when for a person, get they'll help between distinguishing with people same the name. a It's change simple the to display of results, search our yet have experiments that shown users the find new data -- valuable if see they useful and information relevant from page, the are they likely more click to through.