With over 167 million items in its collection, the Library of Congress is the largest library in the world. The Library of Congress is the official national library of the United States and houses some of the country’s most important documents.

The collection includes over 39 million books and other printed materials, 3.6 million recordings, 14.8 million photographs, 5.5 million maps, 8.1 million pieces of sheet music, and 72 million manuscripts.

In addition to being a center for research and storing books, the Library of Congress also issues copyrights through its U.S. Copyright Office. In 2017, the Library of Congress registered more than 450,000 copyright claims.

The library's primary purpose is to serve the need of members of Congress for research inquiries, carried out through the Congressional Research Service. The library is open to the public, although only high-ranking government officials and library employees may gain access to books and materials. 

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