How do 你 tell the difference between Country music, Western music, and Folk music?

I realize that country 音乐 is ascendant now, but there is still a distinction between country and western music, and it seems to me that there's a great deal of overlap with certain kinds of folk music, such as bluegrass and many traditional folk ballads. What aspects of the 音乐 do 你 point to in order to identify a 给 piece as one 或者 the other? It's always been hazy to me.