Rhythm and blues, often abbreviated to R&B, is a genre of popular African American music that originated in the 1940s. The term was originally used by record companies to describe recordings marketed predominantly to urban African Americans, at a time when "urbane, rocking, jazz based music with a heavy, insistent beat" was becoming more popular. The term has subsequently had a number of shifts in meaning. In the early 1950s and beyond, the term rhythm and blues was frequently applied to blues records. Starting in the 1950s, after this style of music contributed to the development of rock and roll, the term "R&B" became used to refer to music styles that developed from and incorporated electric blues, as well as gospel and soul music. By the 1970s, rhythm and blues was used as a blanket term for soul and funk. In the 1980s, a newer style of R&B developed, becoming known as contemporary R&B.

The migration of African Americans to the urban industrial centers of Chicago, Detroit, New York, Los Angeles and elsewhere in the 1930s created a new market for jazz, blues, and related genres of music, often performed by full-time musicians, either working alone or in small groups. The precursors of rhythm and blues came from jazz and blues, which overlapped in the 1930s through the work of musicians such as The Harlem Hamfats, with their 1936 hit "Oh Red", as well as Leroy Carr, Cab Calloway, Count Basie, and T-Bone Walker. There was also increasing emphasis on the electric guitar as a lead instrument, as well as the piano and saxophone.

By the 1970s, the term rhythm and blues was being used as a blanket term for soul, funk, and disco. Around the same time, earlier R&B was an influence on British pub rock and later, the mod revival. Now the term R&B is almost always used instead of the full rhythm and blues, and mainstream use of the term usually refers to contemporary R&B, which is a newer version of soul and funk music that originated as disco faded from popularity.