Hot Rats is the second solo album by Frank Zappa. It was released in October 1969. The album consists of six songs, five of which are instrumental (the song "Willie the Pimp" features a short vocal by Captain Beefheart). It was Zappa's first recording project after the dissolution of the original Mothers of Invention. Because it focuses on long instrumental jazz-like compositions with extensive soloing, the music sounds very different than earlier Zappa albums which featured short songs with satirical vocal performances. It features none of the Mothers, save Ian Underwood, who was also the primary collaborator and sideman. In Read more on Last.fm.