OCLC, Inc., a U.S.-based nonprofit cooperative organization, plays a pivotal role in the global library community, largely through its creation and maintenance of WorldCat and the assignment of OCLC Control Numbers (OCNs). These two initiatives represent fundamental contributions to the organization, accessibility, and discoverability of information worldwide. WorldCat, developed in collaboration with thousands of member libraries, stands as the largest
online public access catalog, while OCNs provide essential identifiers for a vast array of bibliographic materials, particularly those predating the widespread use of ISBNs. Together, they form critical components of the modern library infrastructure.
WorldCat: The World's Largest Online Catalog
At the heart of OCLC's services is WorldCat, an expansive online public access catalog that is cooperatively produced and maintained by OCLC and its member libraries. This catalog is unparalleled in its size and scope, offering bibliographic, abstract, and full-text information to users globally. WorldCat aggregates holding records from public and private libraries across the world, providing a comprehensive view of available resources. This collaborative effort means that libraries contribute their cataloging data, enriching the collective resource and making it easier for individuals to locate books, articles, and other materials.
The sheer scale of WorldCat makes it an indispensable tool for researchers, students, and anyone seeking information. Its ability to show what materials are held by which libraries facilitates interlibrary loan and resource sharing, embodying the cooperative spirit of OCLC. The continuous maintenance and updating of WorldCat ensure its relevance and accuracy, reflecting the dynamic nature of library collections and scholarly output. This global catalog serves as a testament to the power of shared technology and community programs in enhancing access to knowledge.
The Significance of OCLC Control Numbers (OCNs)
Beyond WorldCat, OCLC's contribution to information organization is further solidified through its assignment of OCLC Control Numbers (OCNs). These unique identifiers are particularly valuable for bibliographic items that do not possess International Standard Book Numbers (ISBNs), such as many books published before 1970. OCNs provide a consistent and reliable way to identify and track these materials, ensuring they can be effectively managed and discovered within library systems and beyond.
The utility of OCNs extends into major online information platforms, where they are frequently used as identifiers. For instance, OCNs are commonly employed within Wikipedia and Wikidata to help categorize and link bibliographic data. A report from October 2013 highlighted their prevalence, noting that out of 29,673 book infoboxes in Wikipedia, 15,226 included OCNs, alongside 23,304 ISBNs. Similarly, within Wikidata, among approximately 14 million items, 28,741 were books, with OCNs present in 12,262 of these items, outnumbering the 5,403 items that had ISBNs. This widespread integration demonstrates the critical role OCNs play in standardizing and connecting bibliographic information across diverse digital environments, thereby improving the overall discoverability and organization of knowledge.
