The document provides background information on the book "Al Capone Does My Shirts" and the setting of Alcatraz prison. It explains that in 1935, the main character Moose and his family moved to Alcatraz where his father became a prison guard. Alcatraz was opened in 1934 as a federal prison located 1 mile from San Francisco, meant to house problematic prisoners from other facilities who were threats, escape risks, or getting too much media attention. Some of the most famous criminals sent there included Al Capone, George "Machine Gun" Kelly, and Robert "Birdman" Stroud.