World music is a term that covers all music that is not part of mainstream pop music or classical music and has some kind of "ethnic" component. The connotation of the term is pop music from the third world, European pop music that uses influences from the third world, and traditional music especially but not only from the third world. The term is used primarily as a marketing/classificatory device, sometimes referring to any kind of foreign music, especially in a foreign language. Obviously, the various kinds of ethnic music that are included under the rubric "world music" do not have anything in common genetically or musically in virtue of which they are called "world music."
... maximum effect when the axis starts "rolling" inside the groove. (Compare with graphic below.) Since this friction force is essential for the device's operation, the groove ...