Bob Dylan's force was evident during his peak popularity in the '60s, but his influence echoed throughout subsequent generations. Many of his songs became popular standards, and his best albums are undisputed classics. He marks a pivotal turning point in the 20th century evolution of folk music, when the genre moved away from traditional songs. As a songwriter, he pioneered several different schools, from confessional singer/songwriter to stream-of-conscious narratives. As a vocalist, he broke down the notion that a singer had to have a conventionally good voice in order to perform. As a musician, he sparked several genres, including electrified folk-rock and country-rock.