A style of music developed from 80s
hardcore. Pioneered by such bands as Napalm Death, and Carcass among others.
The music is characterized with very
fast guirar riffs, and
even faster drums, together with incomprehensible vocals (Some bands use high pitched screaming, some use
low pitched growling).
Contrary to popular belief, Grindcore IS NOT METAL. Some bands are, if they are mixing in elements of Death, Black, or other forms of metal, but Grindcore itself is not metal, since it evolved from punk music, and not any style of metal.