Roger Keith "Syd" Barrett (6 January 1946 – 7 July 2006) was an English singer, songwriter, and musician who co-founded the rock band Pink Floyd in 1965. Characterised for his English-accented singing and free-form writing style, Barrett named the group and was their original lead singer, guitarist and principal songwriter. His innovative use of guitar techniques, such as dissonance, distortion and feedback, proved influential to many musicians.
Barrett was musically active for less than ten years. With Pink Floyd, he recorded four singles, their debut album The Piper at the Gates of Dawn (1967), portions of their second album A Saucerful of Secrets (1968), and several unreleased songs. In April 1968, Barrett was ousted from the band amid speculation of mental illness and his excessive use of psychedelic drugs. He began his solo career in 1969 with the single "Octopus" from his first solo album The Madcap Laughs (1970). The album was recorded over the course of a year with five different producers, including former Pink Floyd bandmates David Gilmour and Roger Waters. He recorded and released one more album, Barrett (1970), also produced by Gilmour, with contributions from Pink Floyd keyboardist Richard Wright.
In 1972, Barrett left the music industry, retired from public life and strictly guarded his privacy until his death. He continued painting and dedicated himself to gardening. Pink Floyd recorded several tributes and homages to him, including the 1975 song suite "Shine On You Crazy Diamond" and the 1979 rock opera The Wall. In 1988, EMI released an album of unreleased tracks and outtakes, Opel, with Barrett's approval. He died of pancreatic cancer in 2006.