"Liar" is the fifth track (first on side two) and, in some territories, second single of English rock band Queen's first album, Queen.
"Liar (It Takes One To Know One)" is the second single in the U.S. from the rock band, Taking Back Sunday. The song is featured on the band's latest album, Louder Now and will be released in the U.S., while their second single in the UK, Twenty-Twenty Surgery will be released. The music video was released on Thursday, September 28, 2006 on MTV2.