Doo Wop was one of the most popular genres of rock & roll and R&B in the late '50s. Doo wop artists were vocal groups, with each singer in the group taking a different part that interweaved with the other singers. Frequently, the backing vocalists sang nonsense words as rhythm, and the genre's name derives from this trait. Most doo wop groups started as a cappella bands, performing without instrumental accompaniment. The hit doo wop singles inspired countless teenagers to form their own a cappella groups, though many of them were never recorded. Despite its a cappella origins, few doo wop records were made without instrumental backing. Doo wop faded away in the early '60s, though its influence was felt throughout popular music in the following decades.