Glossary
========

.. glossary ::
   :sorted:
   
   Fuseki
      Part of the `Apache Jena project <http://jena.apache.org/>`_, Fuseki
      is Free Software bringing together a :term:`triple store`, a
      :term:`SPARQL` implementation, and the `graph store HTTP protocol
      <http://www.w3.org/TR/sparql11-http-rdf-update/>`_. The Open Data
      Service uses Fuseki for storing and mediating access to the available
      data.

   linked data
      A pattern for publishing data on the web using URIs as identifiers, so
      that it can be interlinked and thus gain greater utility by becoming
      part of the *web of data* (by analogy to the human-readable *web of
      documents*). See `the Wikipedia article
      <http://en.wikipedia.org/wiki/Linked_data>`_ for more information.
      
      If you're just getting started with linked data, the Open Data Team at
      Southampton have put together this `useful guide for beginners
      <http://openorg.ecs.soton.ac.uk/wiki/Linked_Data_Basics_for_Techies>`_.

   N-Triples
      A simple :term:`RDF serialization`, and a subset of :term:`Turtle` (i.e.
      every N-Triples file is also valid Turtle). Often used for streaming RDF
      data between systems. See `the Wikipedia page
      <http://en.wikipedia.org/wiki/N-Triples>`_ for more information.

   open data stars
      The stars represent the extent to which a dataset is part of the linked
      open data web. These were the definitions used by Tim Berners-Lee during
      his `Gov 2.0 talk <http://www.youtube.com/watch?v=ga1aSJXCFe0>`_ in 2010,
      and have since become widely accepted as an ideal to work towards.

      .. raw:: html

         <table>
           <tbody>
             <tr>
               <td><img src="https://static.data.ox.ac.uk/desc/stars/data-badge-0.png" alt="0 stars"/></td>
               <td>Data available, but not openly licensed</td>
             </tr>
             <tr>
               <td><img src="https://static.data.ox.ac.uk/desc/stars/data-badge-1.png" alt="1 star"/></td>
               <td>Put your data on the web with an open licence (in any format)</td>
             </tr>
             <tr>
               <td><img src="https://static.data.ox.ac.uk/desc/stars/data-badge-2.png" alt="2 stars"/></td>
               <td>Make it available in a machine readable format (i.e. no image scans!)</td>
             </tr>
             <tr>
               <td><img src="https://static.data.ox.ac.uk/desc/stars/data-badge-3.png" alt="3 stars"/></td>
               <td>Use a open, standard format (eg JSON)</td>
             </tr>
             <tr>
               <td><img src="https://static.data.ox.ac.uk/desc/stars/data-badge-4.png" alt="4 stars"/></td>
               <td>Use an open, linked data format (URIs for everything so people can point to your data)</td>
             </tr>
             <tr>
               <td><img src="https://static.data.ox.ac.uk/desc/stars/data-badge-5.png" alt="5 stars"/></td>
               <td>Link your data to other people’s data</td>
             </tr>
           </tbody>
         </table>

   RDF
      See :term:`Resource Description Framework`.

   RDF/JSON
      A serialization of RDF into JSON. See `the documentation
      <http://docs.api.talis.com/platform-api/output-types/rdf-json>`_
      for more information.

   RDF/XML
      A serialization of RDF into XML. Generally not considered pretty, but
      useful when creating RDF using XML tools. For more information, see
      `this explanation of it's "stripedness" <http://www.w3.org/2001/10/stripes/>`_
      and the `format specification <http://www.w3.org/TR/REC-rdf-syntax/>`_.

      Examples of RDF/XML can be found `here <http://data.ox.ac.uk/doc:oxpoints/31337175.rdf>`_
      and `here <http://data.ox.ac.uk/datasets/?format=rdf>`_.

   RDF serialization
      As RDF is just a data model, it doesn't have any one true concrete
      syntax. RDF triple serializations include:

      * :term:`RDF/XML`
      * :term:`Turtle`
      * :term:`N-Triples`
      * :term:`RDF/JSON`

   Resource Description Framework
      The Resource Description Framework (RDF) is a metadata data model based
      around *subject object predicate* :term:`triples <triple>`. RDF is not
      tied to representing any particular type of information, leading to an
      information infrastructure that works for just about anything.

      RDF is generally queried using :term:`SPARQL`. You can read more about
      RDF at the `W3C <http://www.w3.org/RDF/>`_ and
      `Wikipedia <http://en.wikipedia.org/wiki/Resource_Description_Framework>`_.

   slug
      A relatively short, human-readable sequence of characters used to
      uniquely identify a thing, normally in a URI or URL. These should
      normally be lowercase with punctuation removed, and hyphens used to
      delimit words if applicable.
      Examples include ``course``, ``undergraduate-course``, and
      ``university-of-oxford``. Often one excludes terms such as "the" and
      "and" as they add unnecessary length to the slug. See `the Clean URL
      page on Wikipedia <http://en.wikipedia.org/wiki/Clean_URL#Slug>`_ for
      more information.

   slugification
      Turning a phrase into a :term:`slug`. For example, one would slugify
      "University of Oxford" to ``university-of-oxford``. Slugification can
      either be done automatically, or with human input.

   SPARQL
      A query language for RDF databases. SPARQL queries can return table-like
      results (like SQL ``SELECT`` queries), or :term:`RDF <Resource Description Framework>`.

      Cambridge Semantics' `SPARQL by Example
      <http://www.cambridgesemantics.com/2008/09/sparql-by-example/>`_ provides
      a good introduction to the language. `answers.semantic.web
      <http://answers.semanticweb.com/>`_ is also a good resource if you get
      stuck.

      The Open Data Service supports all of
      `SPARQL 1.1 <http://www.w3.org/TR/sparql11-query/>`_ through `Jena ARQ
      <http://jena.apache.org/documentation/query/index.html>`_.

   triple
      An atom of information in `RDF <Resource Description Framework>`. A
      triple consists of a subject, predicate and object, such as "Alice (S)
      knows (P) Bob (O)". These units of information are then composed to
      produce.

   triple store
      A triple store is a database for storing RDF. See `the Wikipedia article
      <http://en.wikipedia.org/wiki/Triplestore>`_ for more information.

   Turtle
      An :term:`RDF serialization` which is generally found to be
      more comprehensible to humans than :term:`RDF/XML`. See `the Wikipedia
      article <http://en.wikipedia.org/wiki/Turtle_%28syntax%29>`_ for a more
      in-depth explanation.

   URI
      In RDF, URIs (Uniform Resource Identifiers) are used to refer to both
      documents on the web (web pages, images, etc) and things. By each being
      globally unique we are able to create a commonly vocabulary in which to
      describe the world around us. See the Wikipedia section on `resource
      identification <http://en.wikipedia.org/wiki/Resource_Description_Format#Resource_identification>`_
      for more information.

   vocabulary
      A set of :term:`URI` terms that have a commonly-understood interpretation
      and so can be used to describe things in RDF. A vocabulary generally
      has one particular focus, e.g. describing organisations, relationships,
      or offers to sell products. There are sites such as `Schemapedia
      <http://schemapedia.com/>`_ and `prefix.cc <http://prefix.cc/>`_ which
      help with finding vocabularies.