A database of more than 55 million records (as of mid-2004) for the bibliographic description of separately cataloged works from thousands of libraries (formerly called the OCLC Online Union Catalog or OLUC). WorldCat is the result of the ongoing cooperative efforts of member libraries worldwide who contribute the records. OCLC products and services that help libraries serve their users are based on WorldCat.

a cooperative catalog of libraries worldwide

The central asset of OCLC. The WorldCat database is the most consulted database in higher education. It holds over 48 million cataloging records created by libraries around the world, with a new record added every 15 seconds. The records span over 4,000 years of recorded knowledge with 400 languages represented. It also includes more than 800 million location listings.