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Data strategy

Support research where it happens.

Research habits have changed. It’s no longer enough for libraries to simply maintain information resources for users to access. They now have to make the information visible to seekers where they begin their research. WorldCat provides libraries with an opportunity to display their holdings on websites beyond library catalogs in a format that search engines, citation management systems, campus platforms, research portals and other information websites can read and repurpose.

three images of individuals on laptops or tablets
Matthijs van Otegem [photo]

“No entry point…”

“First, we had a building and information, and we expected people to come to our building. Then, we digitized, and we expected people to come to our website. There's no entry point anymore. …It's our job to adapt.”

Matthijs van Otegem
Managing Director
Erasmus University Rotterdam
Rotterdam, South Holland, Netherlands

WorldCat’s unique role with linked data

Jay Weitz [photo]

“Most trusted sources…”

“Historically, libraries are among the most trusted sources of accurate information. As we’ve moved toward a linked data future, that institutional legacy of authoritative data has become increasingly important. At OCLC, my colleagues and I take that deeply to heart. We don’t succeed in every case, but our goal is and always has been the continual improvement of bibliographic and authority data for a world increasingly reliant on those data.”

Jay Weitz
Senior Consulting Database Specialist, Data Services and WorldCat Quality Management
Dublin, Ohio, United States

The library data in WorldCat encodes some of the most important, unique and authoritative information sources in the world. When this information can be referenced on the web as “entities” with interconnected relationships, the data can be read and embedded in more websites and online tools than traditionally formatted bibliographic data. Librarians can do more with their data to drive attention back to libraries from more sources, increasing their relevance within the wider information ecosystem. WorldCat houses more library data than any other source and is constantly evolving to keep up with the changing nature of online research habits.

OCLC works closely with other organizations, such as the Library of Congress, schema.org, W3C and other data standards groups, to participate in linked data discussions and initiatives, ensuring that library data are included on the web. By cooperating with other organizations and making WorldCat data available to them, we both enhance the value of WorldCat and ensure that libraries have a voice in the future of information management.

See how linked data can help libraries

WorldCat entities are a way to group all versions of a work, place, concept, person, organization, event or other type of data together. WorldCat work entities are available now for developers, and WorldCat person entities are in development.

Get started with linked data

Using linked data to share the world’s knowledge

OCLC has remained at the forefront of discussions about linked data and the future of data integration throughout the web. OCLC Research continues to explore the opportunities that linked data can bring to researchers and libraries. We have conducted an international linked data survey of more than 150 library projects to understand how libraries use linked data and how they want to use it in the future. We have developed new services, such as WorldCat Identities, that create linked data for exposure to search engines. In addition, OCLC Research team members have published various books, chapters and articles on this topic.

Learn more about OCLC Research’s linked data efforts

Initiatives to take data into the future

OCLC continues to enhance products, taking full advantage of the power of WorldCat. Based on our linked data research and pilot programs, we are actively exploring ways to embed linked data relationships into WorldCat to ensure that user searches deliver rich and relevant results. To learn more about WorldCat’s downloadable data sets, visit the OCLC Developer Network.

WorldCat works

In April 2014, OCLC released 197 million WorldCat work entities that bring together multiple manifestations of a resource into one authoritative record. As of March 2017, more than 215 million WorldCat work entities are available. WorldCat work entities connect all descriptions of a work, despite variations in titles, publishers, authors’ names, subject headings and other bibliographic information. By linking these descriptions, library resources are made more discoverable on the popular websites where information seekers begin their searches.

See an example of a WorldCat works entity

WorldCat persons

WorldCat person entities connect related information about specific people into a brief description that includes various formats of the person’s name, creative works that the person has produced, and biographic sources of information about the person. As of March 2017, WorldCat persons include more than 117 million descriptions of authors, directors, musicians and others, which have been mined directly from WorldCat. OCLC recently conducted a linked data pilot program in which libraries used WorldCat persons in their regular workflows.

See an example of a WorldCat person entity

Partnering for the future

OCLC also works with other organizations to lead libraries’ use of linked data. This cooperation helps to ensure that what works for libraries also works for the broader information community.


OCLC continues to work closely with the Library of Congress on the development of BIBFRAME, an evolving model to share and connect bibliographic data, as an active participant in the BIBFRAME pilot. When this standard is more fully tested and widely implemented, we will explore ways to apply it to WorldCat records to unambiguously identify entities and share relationships between entities across the web.


WorldCat entities are marked up in the schema.org vocabulary to allow search engines and other systems to mine and retrieve information from library data. This standard vocabulary, developed and sponsored by leading technology companies, serves as the data language that modern search engines understand best.