How to Publish Linked Data on the Web Tom Heath, Michael Hausenblas, Chris Bizer, Richard Cyganiak, Olaf Hartig Half-day Tutorial at ISWC2008 27th October 2008, Karlsruhe, Germany Objectives Introduce the concept of Linked Data Highlight why you would want to publish Linked Data on the Web Introduce the principles and best practices of publishing Linked Data on the Web Provide an in-depth understanding of the technical design decisions required when publishing Linked Data Demonstrate the consumption of Linked Data from the Web Look ahead to the future Answer your burning Linked Data publishing questions Tutorial Schedule 09:00 – 09:10 Opening 09:10 – 09:40 Introduction: What and Why 09:40 – 10:30 Publishing Linked Data on the Web: How 10:30 – 11:00 Coffee Break 11:00 – 11:40 Publishing Linked Data on the Web: How 11:40 – 12:00 Consuming Linked Data from the Web 12:00 – 12:10 Conclusions and Outlook 12:10 – 12:30 Discussion and Linked Data Clinic ISWC 2008, Tutorial on How to Publish Linked Data on the Web Introduction: What and Why Christian Bizer Freie Universität Berlin Karlsruhe. October 27, 2008 Christian Bizer: How to Publish Linked Data on the Web - Introduction (10/27/2008) Overview 1. From a Web of Documents to a Web of Data Web APIs, Microformats, and Linked Data 2. Linked Data Deployment on the Web What data is out there? 3. Applications What is being done with the data? Christian Bizer: How to Publish Linked Data on the Web - Introduction (10/27/2008) The Classic Web Single global information space Web Search 2. URLs as Browsers Engines globally unique IDs retrieval mechanism 3. HTML as shared content format 4. Hyperlinks HTML HTML HTML hyper- links Shortcomings Content is not well structured You can not ask expressive queries A B C You can not process content within applications Christian Bizer: How to Publish Linked Data on the Web - Introduction (10/27/2008) What do we actually want? Use the Web like a single global database. Christian Bizer: How to Publish Linked Data on the Web - Introduction (10/27/2008) Solution Publish structured data directly on the Web. Different Approaches 2. Web APIs 3. Microformats 4. Linked Data Christian Bizer: How to Publish Linked Data on the Web - Introduction (10/27/2008) Web APIs Christian Bizer: How to Publish Linked Data on the Web - Introduction (10/27/2008) Mashups Mashup Up Positive 2. APIs expose structured data 3. APIs enable new applications Web Web Web Web API API API API Negative 6. Proprietary interfaces 7. Mashups are based only on fixed set of sources A B C D 8. You can not set hyperlinks between data objects Christian Bizer: How to Publish Linked Data on the Web - Introduction (10/27/2008) Web APIs slice the Web into separate data silos Image: Bob Jagensdorf, http://flickr.com/photos/darwinbell/, CC-BY Christian Bizer: How to Publish Linked Data on the Web - Introduction (10/27/2008) Microformats Embed structured data into HTML pages. hCard, hCalender, hReview, XFN, … <div class="vevent"> <span class="summary">bdigital</span> <abbr class="dtstart" title="2008-05-20">May 20</abbr> - <abbr class="dtend" title="2007-05-22">22</abbr> </div> Compatible with the idea of the Web as single information space. Shortcomings Only a fixed set of microformats exist. No way to connect data items. Christian Bizer: How to Publish Linked Data on the Web - Introduction (10/27/2008) Linked Data Use Semantic Web technologies to 2. publish structured data on the Web, 3. set links between data from one data source to data within other data sources. Thing Thing Thing Thing Thing Thing Thing Thing Thing Thing typed typed typed typed links links links links A B C D E Christian Bizer: How to Publish Linked Data on the Web - Introduction (10/27/2008) Linked Data Principles 1. Use URIs as names for things. 2. Use HTTP URIs so that people can look up those names. 3. When someone looks up a URI, provide useful RDF information. 4. Include RDF statements that link to other URIs so that they can discover related things. Tim Berners-Lee 2007 http://www.w3.org/DesignIssues/LinkedData.html Christian Bizer: How to Publish Linked Data on the Web - Introduction (10/27/2008) The RDF Data Model rdf:type pd:cygri foaf:Person foaf:name Richard Cyganiak foaf:based_near dbpedia:Berlin Christian Bizer: How to Publish Linked Data on the Web - Introduction (10/27/2008) Data objects are identified with HTTP URIs rdf:type pd:cygri foaf:Person foaf:name Richard Cyganiak foaf:based_near dbpedia:Berlin pd:cygri = http://richard.cyganiak.de/foaf.rdf#cygri dbpedia:Berlin = http://dbpedia.org/resource/Berlin Christian Bizer: How to Publish Linked Data on the Web - Introduction (10/27/2008) Dereferencing URIs over the Web rdf:type pd:cygri foaf:Person foaf:name 3.405.259 Richard Cyganiak dp:population foaf:based_near dbpedia:Berlin skos:subject dp:Cities_in_Germany Christian Bizer: How to Publish Linked Data on the Web - Introduction (10/27/2008) Dereferencing URIs over the Web rdf:type pd:cygri foaf:Person foaf:name 3.405.259 Richard Cyganiak dp:population foaf:based_near dbpedia:Berlin skos:subject skos:subject dbpedia:Hamburg dp:Cities_in_Germany dbpedia:Muenchen skos:subject Christian Bizer: How to Publish Linked Data on the Web - Introduction (10/27/2008) The Disco – Hyperdata Browser Christian Bizer: How to Publish Linked Data on the Web - Introduction (10/27/2008) Christian Bizer: How to Publish Linked Data on the Web - Introduction (10/27/2008) 2. Linked Data Deployment on the Web Is this real? Thing Thing Thing Thing Thing Thing Thing Thing Thing Thing typed typed typed typed links links links links A B C D E Christian Bizer: How to Publish Linked Data on the Web - Introduction (10/27/2008) W3C Linking Open Data Project Community effort to publish existing open license datasets as Linked Data on the Web interlink things between different data sources Christian Bizer: How to Publish Linked Data on the Web - Introduction (10/27/2008) LOD Datasets on the Web: May 2007 Christian Bizer: How to Publish Linked Data on the Web - Introduction (10/27/2008) LOD Datasets on the Web: August 2007 Christian Bizer: How to Publish Linked Data on the Web - Introduction (10/27/2008) LOD Datasets on the Web: February 2008 Christian Bizer: How to Publish Linked Data on the Web - Introduction (10/27/2008) LOD Datasets on the Web: September 2008 Christian Bizer: How to Publish Linked Data on the Web - Introduction (10/27/2008) Spotlight: Geonames over 8 million geographical locations feature hierarchy Christian Bizer: How to Publish Linked Data on the Web - Introduction (10/27/2008) Spotlight: DBpedia extracts structured data from Wikipedia. covers over 2.2 million concepts from various domains. h t t p : / / e n . w i k i p e d i a . o r g / w i k i / C a l g a r y < h t t p : / / d b p e d i a . o r g / r e s o u r c e / C a l g a r y > d b p e d i a : n a t i v e _ n a m e “ C a l g a r y ” ; d b p e d i a : a l t i t u d e “ 1 0 4 8 ” ; d b p e d i a : p o p u l a t i o n _ c i t y “ 9 8 8 1 9 3 ” ; d b p e d i a : p o p u l a t i o n _ m e t r o “ 1 0 7 9 3 1 0 ” ; m a y o r _ n a m e d b p e d i a : D a v e _ B r o n c o n n i e r ; g o v e r n i n g _ b o d y d b p e d i a : C a l g a r y _ C i t y _ C o u n c i l ; . Christian Bizer: How to Publish Linked Data on the Web - Introduction (10/27/2008) Example RDF Links RDF links from DBpedia to other data sources <http://dbpedia.org/resource/Berlin> owl:sameAs <http://sws.geonames.org/2950159> . <http://dbpedia.org/resource/Tim_Berners-Lee> owl:sameAs <http://www4.wiwiss.fu-berlin.de/dblp/resource/person/100007> . RDF link from a FOAF profile to DBpedia <http://richard.cyganiak.de/foaf.rdf#cygri> foaf:topic_interest <http://dbpedia.org/resource/Semantic_Web> . Christian Bizer: How to Publish Linked Data on the Web - Introduction (10/27/2008) Organizations publishing Linked Data Universities and Research Institutes Massachusetts Institute of Technology (USA) University of Southampton (UK) Freie Universität Berlin (DE) Companies DERI (IRE) BBC (UK) KMi, Open University (UK) OpenLink (UK) University of London (UK) Zitgist (USA) Universität Hannover (DE) Talis (UK) University of Pennsylvania (USA) Garlik (UK) Universität Leipzig (DE) Mondeca (FR) Universität Karlsruhe (DE) Cyc Foundation Joanneum (AT) (USA) University of Toronto (CA) Christian Bizer: How to Publish Linked Data on the Web - Introduction (10/27/2008) The Bio2RDF Project Goals 1. Make bioinformatics data available in RDF format on the Web. 2. Promote the linked data vision within the bioinformatics community. 3. Answer questions which were not possible or practical to ask before. Participants Université Laval, Canada Queensland University of Technology, Australia Christian Bizer: How to Publish Linked Data on the Web - Introduction (10/27/2008) The Bio2RDF Cloud 27 data sources 260 million records 2,7 billion RDF triples Christian Bizer: How to Publish Linked Data on the Web - Introduction (10/27/2008) The Linking Open Drug Data Effort W3C HCLSIG task started October 1st, 2008 Goal: Publish and interlink data sets about drugs and clinical trials.