Any music with a sharp, strong rhythm is dance music. It makes the body want to move to the beat.

Until there was electronic sound reproduction no one would have listened to such music except when dancing, since they'd have had to pay for a dance band to play for them. But now we have to listen to it even in the supermarket.

A body that resists that urge to move with the beat is under stress and eventually becomes tense. And tension often leads to irritation, anger and aggression.