The Four Seasons is an American rock and pop band that became internationally successful in the 1960s and 1970s. The Vocal Group Hall of Fame has stated that the group was the most popular rock band before the Beatles. Since 1970, they have also been known at times as Frankie Valli and the Four Seasons. In 1960, the group known as the Four Lovers evolved into the Four Seasons, with Frankie Valli as the lead singer, Bob Gaudio (formerly of the Royal Teens) on keyboards and tenor vocals, Tommy DeVito on lead guitar and baritone vocals, and Nick Massi on electric bass and bass vocals.