The Library Corporation (TLC) has its collection of 21 MARC (MAchine-Readable Cataloging) manuals and other reference works relating to library technical services freely available on the web. Library of Congress publications and the Anglo-American Cataloguing Rules (AACR2) were the basis for the content and arrangement of many of the manuals contained at this site. There are cataloging manuals for specific formats, including "archival moving images," looseleaf publications, serials (CONSER), rare books, maps, and graphic materials. In addition, there are guides to USMARC formats for bibliographic, authority, classification, and holdings data. For detailed descriptions and examples of all MARC fields and their subfields, choose "Bibliographic Data" from the main menu and then follow the "Tag List" link. USMARC code lists for countries, geographic areas, and languages are also available.