The Library of Congress occupies three buildings on Capitol Hill. The Thomas Jefferson Building (1897) is the original separate Library of Congress building. (The Library began in 1800 inside the U.S. Capitol.) The John Adams Building was built in 1938 and the James Madison Memorial Building was completed in 1981.
An agency of the legislative branch of the U.S. government, the Library includes several internal divisions (or service units), including the Office of the Librarian, Congressional Research Service, U.S. Copyright Office, Law Library of Congress, Library Services, the Office of Strategic Initiatives and the Office of Support Operations.Today's Library of Congress is an unparalleled world resource. The collection of more than 160 million items includes more than 37.8 million cataloged books and other print materials in 470 languages; more than 69.6 million manuscripts; the largest rare book collection in North America; and the world's largest collection of legal materials, films, maps, sheet music and sound recordings.