It is music for a dance called the two-step.

VOA: special.2010.01.24

Is this conjunct music--step-wise music-- or jumpy, skippy music?

这是级进的音乐,连续的音乐呢,还是轻快,跳跃的音乐呢

耶鲁公开课 - 聆听音乐课程节选