'Paranoid' is the second studio album from Black Sabbath. Released in September 1970, it was the band's only LP to top the UK Albums Chart until the release of the '13' album in 2013. Paranoid contains several of the band's signature songs, including "Iron Man", "War Pigs" and the title track, which was the band's only Top 20 hit, reaching number 4 in the UK charts. It is often cited as the most influential album in the development of the entire heavy metal genre.