What is the difference between a club and a bar?

Lounges are more for socializing, so more seating and little to no dance floor and don't usually have cover charges. Nightclubs are mostly for dancing (hence a bigger dance floor) and usually have cover charges.

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A nightclub normally has a bar, a dance floor and a DJ booth. The music is either a live band or, more commonly, a mix of songs played by a DJ.