The Marvelettes were an American girl group formed in 1960, known for their contributions to the Motown sound. They gained fame with their hit single "Please Mr. Postman," which became the first song by a girl group to reach number one on the Billboard Hot 100 chart. The group originally consisted of members Gladys Horton, Wanda Young, Georgeanna Tillman, Juanita Cowart, and Ann Bogan. Throughout the 1960s, the Marvelettes released several successful songs, including "Don't Mess with Bill" and "Beechwood 4-5789." Their music combined elements of R&B and pop, helping to shape the girl group genre. Despite lineup changes and a decline in popularity by the late 1960s, the Marvelettes remain an influential part of music history.