Daryl Hall & John Oates, commonly known as Hall & Oates, were an American rock duo formed in Philadelphia in 1970. Daryl Hall was generally the lead vocalist; John Oates primarily played the electric guitar and provided backing vocals. The two wrote most of the songs they performed, either separately or in collaboration. They achieved their greatest fame from the mid-1970s to the late 1980s with a fusion of rock and roll, soul music, and rhythm and blues.