WorldCat (the OCLC Online Union Catalog)

OCLC catalog of books, web resources, and other materials worldwide By OCLC
- A global union catalog of libraries
- Contains 330 million (330,000,000 and growing) records cataloged by OCLC member libraries. 
- More than 2.2 billion (2,200,000,000) holdings, each indicating a library where the library information resource can be located 
- Includes records representing more than 400 languages