Short for "Grindcore."
Grindcore, or "grind" for short is a type of very fast speed/thrash metal,
death metal, or
hardcore punk or perhaps a combination of both(depending on how the band plays it). Grind is characterized by very fast drumming that makes predominant use of the blastbeat, very fast thrash metal-style guitar playing, growling/screaming vocals(much like in
death metal), and
usually rather short songs. The world's shortest song ever is "You Suffer," a grind song written and recorded by grind pioneers Napalm Death. This song only lasts 1 to 4 seconds and its lyrics are "You suffer. But why?"
And despite what many people may think, the British bands Napalm Death and Carcass did not really invent grind. Napalm Death named the genre. Grind is actually an American invention, started in the mid-eighties by Repulsion, a death metal band from
Mississippi who wanted to create their own style of brutal music. In 1986, they've released the world's first full-length grind album, "Horrified." Their style of metal was later copied by bands such as Napalm Death and Carcass and the genre still goes on today, though it has never gotten to the mainstream. Still, it's much better than all the nu-metal crap that has plagued the music world since the mid-90s.