OCLC Linked Data
OCLC has been working with Linked Data for several years. As can be seen from the publishing of the Dewey Decimal Classification (DDC), the Virtual International Authorities File (VIAF) and Faceted Application of Subject Terminology (FAST) as linked data. The release of experimental WorldCat Linked Data in June 2012 was another milestone in the exposure of WorldCat.org bibliographic metadata as linked data.
The OCLC linked data strategy is an evolving mix of Linked Open Data (LOD) and Linked Enterprise Data (LED). This means that we will have incremental releases of new data and services, as we better understand how to model and publish the information.
The next step on this evolutionary journey into linked data is the production release of WorldCat Works; the first entity in a series of WorldCat linked data releases.
WorldCat Linked Data
The bibliographic metadata found in WorldCat contains a rich set of objects that can be represented in linked data. Extracting entities like works, persons, and places from that metadata will create a foundation of WorldCat linked data, which will support the introduction of Web services that offer a range of functionality and access to the data.
The Schema.org ontology, extended by other ontologies as needed, is being used as a basis for modeling WorldCat bibliographic data. This provides fullest coverage, improved functionality, and better consumption of this data for our harvest partners and library members looking to do more with structured data exposed within HTML pages (via RDFa 1.1). More detailed information about the vocabulary used by WorldCat.org linked data is available.
Using the Data
WorldCat linked open data provides access to WorldCat published using Linked Data Principles and made available through both machine and human-readable data interfaces. Although it is expected that the true use of this data will be by software applications and other linked data aggregations, we also believe it is important for humans to be able to see the data in an easy-to-understand way. Thus, we are providing a view to the data through a Linked Data Explorer interface.
OCLC identifiers, and Linked Data URIs, are always in the public domain. Independent of the data and/or information content (which may be subject to individual licensing terms open or otherwise) that they identify, or link to, OCLC identifiers (e.g. OCLC Numbers, VIAF IDs, or WorldCat Work URIs) can be treated as if they are in the public domain and can be included in any data exposure mechanism or activity as public domain data
Over the next several months, OCLC’s other core entities will become available as linked open data. We'll document our progress on the WorldCat Entities page. Watch for announcements and additional documentation on tutorials, examples and solution guides.