It depends if it's a single or a double bar line.
if it's a double bar line it's just there to separate the sections of the music and if it's a single bar line all it does it separate the beats in order to make a measure.
Music, design, and drama have all played important roles in the evolution of dance, and in many cultures dance has actually been inseparable from these arts. The Greek word mousikē, for example, referring to music, poetry, and dance as one form, reflected the integral relation between these three arts in classical Greek drama. In the early European ballets, dance, music, drama, and spectacle were equally inseparable.
