Swing music is a style of jazz that developed in the United States during the late 1920s and early 1930s. It became nationally popular from the mid-1930s. The name derived from its emphasis of the off-beat, or nominally weaker beat. Swing bands usually featured soloists who would improvise on the melody over the arrangement. The danceable swing style of big bands and bandleaders such as Benny Goodmanwas the dominant form of American popular music from 1935 to 1946, known as the swing era. The verb "to swing" is also used as a term of praise for playing that has a strong groove or drive. Musicians of the swing era include Duke Ellington, Benny Goodman, Count Basie, Cab Calloway, Jimmy Dorsey, Tommy Dorsey, Woody Herman, Harry James, Lionel Hampton, Glenn Miller, Artie Shaw and Django Reinhardt.
Swing has its roots in 1920s dance music ensembles, which began using new styles of written arrangements, incorporating rhythmic innovations pioneered by Louis Armstrong, Coleman Hawkins, Benny Carter and other jazzmen. During the World War II era Swing began to decline in popularity, and after war, bebop and jump blues gained popularity.
Swing dance is a group of social dances that developed with the swing style of jazz music in the 1920s–1940s, with the origins of each dance predating the popular "swing era". Hundreds of styles of swing dancing were developed; those that have survived beyond that era include Lindy Hop, Balboa, Collegiate Shag, and Charleston. Today, the best-known of these dances is the Lindy Hop, which originated in Harlem in the early 1930s. While the majority of swing dances began in African American communities as vernacular African American dances, some influenced swing-era dances, like Balboa, developed outside of these communities.
"Swing dance" was not commonly used to identify a group of dances until the latter half of the 20th century. Historically, the term "Swing" referred to the style of jazz music, which inspired the evolution of the dance. Jitterbug is any form of swing dance, though it is often used as a synonym for the six-count derivative of Lindy Hop called "East Coast Swing". It was also common to use the word to identify a kind of dancer (i.e., a swing dancer). A "jitterbug" might prefer to dance Lindy Hop, Shag, or any of the other swing dances. The term was famously associated with swing era band leader Cab Calloway because, as he put it, "[The dancers] look like a bunch of jitterbugs out there on the floor due to their fast, often bouncy movements."
The term "swing dancing" is often extended to include other dances that do not have certain characteristics of traditional swing dances: West Coast Swing, Carolina Shag, East Coast Swing, Hand Dancing, Jive, Rock and Roll, Modern Jive, and other dances developed during the 1940s and later. A strong tradition of social and competitive boogie woogie and Rock 'n' Roll in Europe add these dances to their local swing dance cultures.