Roy Harper (born 12 June 1941) is an English folk / rock singer-songwriter and guitarist who has been a professional musician since the mid 1960s. He has released a large catalogue of albums as an artist (22 studio albums and 12 live albums) and his influence has been acknowledged by many musicians including Jimmy Page and Robert Plant of Led Zeppelin (who named the song "Hats Off to (Roy) Harper" after him), Pink Floyd (who invited him to sing guest lead vocals on their song "Have a Cigar")