WorldCat is a union catalog that itemizes the collections of 72,000 libraries in 170 countries and territories that participate in the Online Computer Library Center (OCLC) global cooperative. It is operated by OCLC Online Computer Library Center, Inc. The subscribing member libraries collectively maintain WorldCat's database, the world's largest bibliographic database. 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).
