Bee Gees were a musical group which originally comprised three brothers: Barry, Robin, and Maurice Gibb. The trio were successful for most of their decades of recording music, but they had two distinct periods of exceptional success: as a pop act in the late 1960's / early 1970's, and as prominent performers of the disco music era in the late 1970's. The group sang three-part tight harmonies that were instantly recognisable; Robin's clear vibrato lead was a hallmark of their earlier hits, while Barry's R&B falsetto became their signature sound during the late 1970's and 1980's. The brothers wrote all of their own hits, as well as writing and producing several major hits for other artists.