Underground I
A genre in music and other forms of media intended for an elite audience, that is often characterized by its high levels of originality and experimentation, and does not conform to typical standards, trends, or hypes as set by the popular mainstream media. The mainstream media has a tendency to steal new ideas from the underground.
Underground II
Art, opinion ororganization that exists outside of mainstream society or culture. Also known as "independent" or sometimes "counter-culture". Giff preferred the underground music scene in her area to the bland stuff that played on most radio stations.
Underground III
Underground is like deeper beats, lyrics and soul to a song - commercial is like what get's played on the radio and is marketed to the masses - Britney's mainstream, Eminem is mainstream - even though anyone can make underground music they don't coz it doesn't sell like commercial stuff - underground IS deeper, more hardcore, more controversial, or whatever...
Sub Underground
It about everything , not only a music. It such as a movement with in people get together trying to built a DIY comunity and doing something right thing to show their protest in kind of clean ways. This to be not jugde any party, movement, religion, individu. It some kinds of opposition low count comunity.