The Library of Congress is America's national library. It has more than 120 million books and other objects. It has newspapers, popular publications and letters of historical interest. It also has maps, photographs, art prints, movies, sound recordings and musical instruments. The Library of Congress is open to the public Monday through Saturday, except for government holidays. Anyone may go there and read anything in the collection. But no one is permitted to take books out of the building. The Library of Congress provides books and materials to the United States Congress. It also lends books to other American libraries, government agencies and foreign libraries. It buys some of its books and gets others as gifts. It also gets materials through its copyright office. Anyone who wants copyright protection for a publication must send two copies to the library. This means the Library of Congress receives almost everything published in the United States.