R&B is short for “rhythm and blues,” and it's a popular music genre originating back in the 1940s. In the '50s through '70s, record companies used the term R&B to describe “urbane, rocking, jazz based music with a heavy, insistent beat.” In that time, R&B bands usually had a piano, one or two guitars, bass, drums, a saxophone, and background vocalists. In the '80s, a newer style of R&B was introduced, combining elements of funk, pop, hip-hop, and dance.
Popular R&B singers at the end of the 20th century included Prince, Michael Jackson, Stevie Wonder, and Mariah Carey. In the late '80s and early '90s, hip-hop captured the ears of American youth, making it difficult for R&B artists to have their music heard. Therefore, artists such as Usher, R. Kelly, TLC, Beyonce, and Mary J. Blige adapted a hip-hop image, occasionally featuring rappers on their songs.
This is a trend continuing with pop starts to this day. 2004 was a peak year for R&B popularity, as 80% of the songs topping the R&B charts were also on top of the Hot 100. From approximately 2005 to 2013, R&B sales declined, but since 2010, hip-hop adapted a smoother, softer sound incorporating that of traditional R&B with rappers such as Drake and Fetty Wap. This sound grew popular and created controversy for both Hip-Hop and R&B in how to identify it.