Doo Wop
Doo-Wop is form of rock-n-roll that features a tenor as a lead vocalist singing the melody of the song with a trio or a quartet singing background harmony. The term doo-wop came from the sounds made by the group as they provide harmonic background for the lead singer (britanica)
Frankie Lymon & The Teenagers
Frankie Lymon and the doo-wopping teenagers rose to fame in 1956 with their hit "Why Do Fools Fall in Love".
The Orioles
The Orioles were a successful and influential vocal group who established the basic pattern for the doo-wop sound (wikipedia)
The Platters
The Platters were on of the top vocal groups of the 1950's, selling 53 million records and being one of the first doo-wop groups inducted into the Rock and Roll Hall of Fame in 1990.