Cowboy Bebop has been strongly influenced by American music, especially the jazz movements of the 1940s, 1950s and 1960s and the early rock era of the 1950s, 1960s and 1970s. Many of its action sequences, from space battles to hand-to-hand martial arts combat, are set and timed to music. Following the musical theme, episodes are called Sessions, and titles are often borrowed from album or song names (such as Sympathy for the Devil or My Funny Valentine), or make use of a genre name ("Mushroom Samba") indicating a given episode's musical theme.