Schema.org

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Schema.org
Year started 2011
Organization Google, Yahoo, Microsoft, Yandex
Base standards URI, HTML5, RDF, Microdata, ISO 8601
Related standards RDFa, Microformat, RDFS, OWL, N-Triples, Turtle, JSON, JSON-LD, CSV
Domain Semantic Web
License CC-BY-SA 3.0
Abbreviation schema
Website schema.org

Schema.org is an initiative launched on 2 June 2011 by Bing, Google and Yahoo![1][2][3] (the operators of the then world's largest search engines)[4] to “create and support a common set of schemas for structured data markup on web pages.” In November 2011 Yandex (whose search engine is the largest one in Russia) joined the initiative.[5][6] They propose using the schema.org vocabulary along with the Microdata, RDFa, or JSON-LD formats[7] to mark up website content with metadata about itself. Such markup can be recognized by search engine spiders and other parsers, thus gaining access to the meaning of the sites (see Semantic Web). The initiative also describes an extension mechanism for adding additional properties.[8] Public discussion of the initiative largely takes place on the W3C public vocabularies mailing list.[9]

Much of the vocabulary on schema.org was inspired by earlier formats such as Microformats, FOAF, GoodRelations and OpenCyc.[10] Microformats, with its most dominant representative hCard, continue to be published widely in the Web, where the deployment of schema.org has strongly increased between 2012 to end 2014.[11]

RDF applications can use Microdata2RDF service.[12] getSchema[13] is a community wiki maintaining a set of markup examples.

A mapping from the terms defined in Schema.org to RDF (expressed in RDF Schema) is available.[14]

To test the validity of the data marked up with the schemas and Microdata, such validators as the Google Structured Data Testing Tool,[15] Yandex Microformat validator[16] and Bing Markup Validator[17] can be used.

Some Schema markups such as Organization and Person are used to influence Google's Knowledge Graph results.[18]

Examples

Microdata

The following is an example[19] of how to mark up information about a movie and its director using the schema.org schemas and microdata. In order to mark up the data the attribute itemtype along with the URL of the schema is used. The attribute itemscope defines the scope of the itemtype. The kind of the current item can be defined by using the attribute itemprop.

<div itemscope itemtype="http://schema.org/Movie">
  <h1 itemprop="name">Avatar</h1>
  <div itemprop="director" itemscope itemtype="http://schema.org/Person">
  Director: <span itemprop="name">James Cameron</span> 
(born <time itemprop="birthDate" datetime="1954-08-16">August 16, 1954</time>)
  </div>
  <span itemprop="genre">Science fiction</span>
  <a href="../movies/avatar-theatrical-trailer.html" itemprop="trailer">Trailer</a>
</div>

RDFa 1.1 Lite

<div vocab="http://schema.org/" typeof="Movie">
  <h1 property="name">Avatar</h1>
  <div property="director" typeof="Person">
  Director: <span property="name">James Cameron</span>
(born <time property="birthDate" datetime="1954-08-16">August 16, 1954</time>)
  </div>
  <span property="genre">Science fiction</span>
  <a href="../movies/avatar-theatrical-trailer.html" property="trailer">Trailer</a>
</div>

JSON-LD

<script type="application/ld+json">
{ 
  "@context": "http://schema.org/",
  "@type": "Movie",
  "name": "Avatar",
  "director": 
    { 
       "@type": "Person",
       "name": "James Cameron",
       "birthDate": "1954-08-16"
    },
  "genre": "Science fiction",
  "trailer": "../movies/avatar-theatrical-trailer.html" 
}
</script>

References

  1. Introducing schema.org: Search engines come together for a richer web, Google blog, 2 June 2011
  2. Introducing Schema.org: Bing, Google and Yahoo Unite to Build the Web of Objects, Bing blog, 2 June 2011
  3. Introducing schema.org: A Collaboration on Structured Data, Yahoo blog, 2 June 2011
  4. Lua error in package.lua at line 80: module 'strict' not found.
  5. Techcrunch "Yandex joins Google, Yahoo! and Bing to collaborate on Schema.org"
  6. Schema Blog "Yandex now supports schema.org markup"
  7. Getting started with schema.org using Microdata
  8. Lua error in package.lua at line 80: module 'strict' not found.
  9. Lua error in package.lua at line 80: module 'strict' not found.
  10. Lua error in package.lua at line 80: module 'strict' not found.
  11. Lua error in package.lua at line 80: module 'strict' not found.
  12. Microdata2RDF - a REST service extracting RDF from Microdata semantic annotations
  13. GetSchema.org
  14. Schema.RDFS.org
  15. Google Structured Data Testing Tool
  16. Yandex Microformat validator
  17. Bing Markup Validator
  18. Lua error in package.lua at line 80: module 'strict' not found.
  19. Getting started with schema.org -- Example

External links