Progressive rock (radio format)

Progressive rock is a radio station programming format that emerged in the late 1960s, in which disc jockeys are given wide latitude in what they may play, similar to the freeform format but with the proviso that some kind of rock music is almost always played. It enjoyed the height of its popularity in the late 1960s and 1970s. The name for the format began being used circa 1968, when serious disc jockeys were playing "progressive 'music for the head'" and discussing social issues in between records. During the late 1960s, as long-playing records began to supplant the single in popularity with rock audiences, progressive rock stations placed more emphasis on album tracks than did their AM counterparts.