A jazz club is a venue where the primary entertainment is the performance of live jazz music, although some jazz clubs primarily focus on the study and/or promotion of jazz-music.[1] Jazz clubs are usually a type of nightclub or bar, which is licensed to sell alcoholic beverages. Jazz clubs were in large rooms in the eras of Orchestral jazz and big band jazz, when bands were large and often augmented by a string section. Large rooms were also more common in the Swing era, because at that time, jazz was popular as a dance music, so the dancers needed space to move. With the transition to 1940s-era styles like Bebop and later styles such as soul jazz, small combos of musicians such as quartets and trios were mostly used, and the music became more of a music to listen to, rather than a form of dance music. As a result, smaller clubs with small stages became practical.
In the 2000s, jazz clubs may be found in the basements of larger residential buildings, in storefront locations or in the upper floors of retail businesses. They can be rather small compared to other music venues, such as rock music clubs, reflecting the intimate atmosphere of jazz shows and long-term decline in popular interest in jazz.[2] Despite being called "clubs", these venues are usually not exclusive. Some clubs, however, have a cover charge if a live band is playing. Some jazz clubs host "jam sessions" after hours or on early evenings of the week. At jam sessions, both professional musicians and amateurs will typically share the stage.