WorldCat is a union catalog that itemizes the collections of tens of thousands of institutions (mostly libraries), in many countries, that are current or past members of the OCLC global cooperative.[3] It is operated by OCLC, Inc.[4] Many of the OCLC member libraries collectively maintain WorldCat's database, the world's largest bibliographic database.[5] The database includes other information sources in addition to member library collections.[6] OCLC makes WorldCat itself available free to libraries, but the catalog is the foundation for other subscription OCLC services (such as resource sharing and collection management). WorldCat is used by librarians for cataloging and research and by the general public.
As of December 2021[update], WorldCat contained over 540 million bibliographic records in 483 languages, representing over 3 billion physical and digital library assets,[4] and the WorldCat persons dataset (mined from WorldCat) included over 100 million people.[7]
OCLC was founded in 1967 under the leadership of Fred Kilgour.[8] That same year, OCLC began to develop the union catalog technology that would later evolve into WorldCat; the first catalog records were added in 1971.[8][9]
In 2003, OCLC began the "Open WorldCat" pilot program, making abbreviated records from a subset of WorldCat available to partner web sites and booksellers, to increase the accessibility of its subscribing member libraries' collections.[10][11]
In October 2005, the OCLC technical staff began a wiki project, WikiD, allowing readers to add commentary and structured-field information associated with any WorldCat record.[12] WikiD was later phased out, although WorldCat later incorporated user-generated content in other ways.[13][14]
In 2006, it became possible for anyone to search WorldCat directly at its open website WorldCat.org,[15] not only through the subscription FirstSearch interface where it had been available on the web to subscribing libraries for more than a decade before.[16] Options for more sophisticated searches of WorldCat have remained available through the FirstSearch interface.[15]
In 2007, WorldCat Identities began providing pages for 20 million "identities", which are metadata about names—predominantly authors and persons who are the subjects of published titles.[17]
In 2017, OCLC's WorldCat Search API was integrated into the cite tool of Wikipedia's VisualEditor, allowing Wikipedia editors to cite sources from WorldCat easily.[18][19]
Beginning in 2017, OCLC and the Internet Archive have collaborated to make the Internet Archive's records of digitized books available in WorldCat.[20]
In May 2022, OCLC announced WorldCat Entities, a new infrastructure for library linked data.[21][22] Maintenance of WorldCat Identities was suspended and the service will be discontinued as it is being replaced by WorldCat Entities.[23]
In August 2022, OCLC launched a "redesigned and reimagined" WorldCat.org website with the stated goal "to offer greater accessibility to the collections".[24] The website now requires the use of JavaScript and is therefore no longer accessible for users of older web browsers or those that have JavaScript disabled for security reasons. The update also removed users' book reviews and replaced them with reviews from Amazon subsidiary GoodReads.[25]
In 2023, Anna's Archivescraped and began distributing the whole WorldCat database and was subsequently sued by OCLC in January 2024.[26]
Local catalogs of many OCLC member libraries are intermittently synchronized with the WorldCat database.[27] WorldCat allows participating institutions to add direct links from WorldCat to their own local catalog entries for particular items, which enables the user to click through to the local catalog to quickly determine an item's real-time status (for example, whether or not it is checked out).[28]
In a small percentage of libraries,[29] the local catalog is also run by OCLC using an integrated library system called WorldCat Discovery and WorldShare Management Services.[30]
Library contributions to WorldCat are made via the Connexion computer program,[31] which was introduced in 2001; its predecessor, OCLC Passport, was phased out in May 2005.[32]Cataloging librarians may also use the WorldShare Record Manager[33] or WorldCat Metadata API[34] for similar purposes.[35]
^1998 is the date of registry of the WorldCat.org domain; see: "WorldCat.org WHOIS, DNS, & Domain Info – DomainTools". WHOIS. Archived from the original on June 20, 2019. Retrieved January 21, 2017. However, the union catalog that became WorldCat was started three decades earlier, and it was already available on the web to subscriber libraries at OCLC.org several years before WorldCat.org was a registered domain name; see: "OCLC.org WHOIS, DNS, & Domain Info – DomainTools". WHOIS. Archived from the original on June 26, 2019. Retrieved June 26, 2019.
^The 2012–2013 OCLC Annual Report noted that the number of "participating libraries (includes active and inactive symbols)" was 78,985: 2012–2013 OCLC Annual Report (Report). p. 5. OCLC1226313226. Retrieved March 10, 2022.
^ abMargalit Fox (August 2, 2006). "Frederick G. Kilgour, Innovative Librarian, Dies at 92". The New York Times. Archived from the original on April 25, 2009. Retrieved December 22, 2009. Frederick G. Kilgour, a distinguished librarian who nearly 40 years ago transformed a consortium of Ohio libraries into what is now the largest library cooperative in the world, making the catalogs of thousands of libraries around the globe instantly accessible to far-flung patrons, died on Monday in Chapel Hill, N.C. He was 92.
^Bertot, John Carlo; Berube, Katy; Devereaux, Peter; Dhakal, Kerry; Powers, Stephen; Ray, Jennie (April 2012). "Assessing the usability of WorldCat Local: findings and considerations". The Library Quarterly. 82 (2): 207–221. doi:10.1086/664588. JSTOR10.1086/664588. S2CID61287720. Breeding [2] also makes the following observations about the benefits of the search system: the presence of a more visually appealing interface; the grouping of related material; faceted navigation; and the capability for user-generated content (e.g., reviews). Eden [3] also refers to the advantages of user-generated content possible in WCL...
^Prucha, Francis Paul (1994). "National online library catalogs". Handbook for research in American history: a guide to bibliographies and other reference works (2nd ed.). Lincoln: University of Nebraska Press. pp. 25–27. ISBN0803237014. OCLC28018047. Online Computer Library Center has developed two new programs. One is called EPIC, a new command-driven full online service with sophisticated searching features, including subject searches, intended for librarians and other experienced users. The other, designed for end-users, is FirstSearch, which contains the database materials found in EPIC or subsets of them but has a menu interface that nonspecialists find easy to use. Both EPIC and FirstSearch make available the full OCLC Online Union Catalog (called WorldCat in FirstSearch), but they also function as online database services, offering their users a wide array of other databases.
^"WorldCat Identities". OCLC. March 9, 2023. Archived from the original on March 25, 2023. Retrieved March 15, 2023. The research prototype application is no longer supported or maintained ... We have taken the findings of the research effort and used them to start to build the WorldCat Entities data. These new Entities and their persistent URIs will serve as the foundation for future linked data services similar to those explored in the Identities Research work.
^Schonfeld, Roger C. (December 5, 2019). "What are the larger implications of Ex Libris buying Innovative?". Ithaka S+R. Archived from the original on June 12, 2020. Retrieved April 25, 2020. OCLC's WorldShare cloud system has yet to achieve critical mass, amounting to 10% of the academic market (but only 4% of ARL), and OCLC's entire public library business represents just 10% of the public library market. For another source of statistics on library system market share, see: "Marketshare Report". Library Technology Guides. Archived from the original on July 28, 2021. Retrieved June 18, 2021.
What the OCLC online union catalog means to me: a collection of essays. Dublin, Ohio: OCLC. 1997. ISBN1556532237. OCLC37492023.
Wilson, Kristen (August 2016). "The knowledge base at the center of the universe". Library Technology Reports. 52 (6): 1–35. doi:10.5860/ltr.52n6.
"WorldCat data licensing"(PDF). OCLC. Archived(PDF) from the original on December 31, 2018. Retrieved December 31, 2018. See also: "Data licenses & attribution". oclc.org. January 14, 2017. Archived from the original on December 31, 2018. Retrieved December 31, 2018. Information about licensing of WorldCat records and some other OCLC data.
