"Crossover can also refer to another very popular style that showed up in the early 1990's, when bands would mix together a multitude of pop styles such as funk, hip hop, punk rock, and some heavy metal. This style was initially referred to as funk metal. Some well-known crossover artists are the Red Hot Chilli Peppers and Rage Against The Machine."
http://en.wikipedia.org/wiki/Crossover_%28music%29
Csókolom.

