WorlCat is a union catalog which itemizes the collections of more than 10,000 libraries which participate in the OCLC global cooperative. It is built and maintained collectively by the participating libraries from more than ninety countries. Created in 1971, it contains more than 90 million different records pointing to over 1.2 billion physical and digital assets in more than 360 languages, as of November 2007. It is the world's largest bibliographic database. WorldCat itself is not directly purchased by libraries, but serves as the foundation for many other fee-based OCLC services (such as resource sharing and collection management).