These are repositories for preserving and making available the papers , records , collections and other historical materials of every President of the United States since Herbert Hoover ( 31st President , 1929-1933 ) .
These are offices for preserving and making available the papers , records , collections and other historical materials of every President of the United States . The presidential library system began with Herbert Hoover 's library ( 31st President , 1929-1933 ) .