The Library of Congress Online Catalog contains approximately 14 million records representing books, serials, computer files, manuscripts, cartographic materials, music, sound recordings, and visual materials. The Catalog also displays searching aids for users, such as cross-references and scope notes. The catalog records reside in a single integrated database; they are not separated according to type of material, language of material, date of cataloging, or processing/circulation status.
As an integrated database, the Online Catalog includes 3.2 million catalog records from an earlier database. These catalog records, primarily for books and serials cataloged between 1898 and 1980, are being edited to comply with current cataloging standards and to reflect contemporary language and usage. The legend [from old catalog] indicates that the headings may deviate from current Library of Congress cataloging policy.
Many items from the Library's special collections are accessible to users but are not represented in this catalog. In addition, some individual items within collections (microforms, manuscripts, photographs, etc.) are not listed separately in the Catalog, but are represented by collection-level catalog records.
September 13, 2010