Grindcore is an extreme form of 
heavy metal, related to 
death metal, and pioneered by the 
British band 
Napalm Death in the early 
1980s. Since then, the grind sound has evolved but is still recognisable by its intense 
blast-beat sound, grinding guitars (hence the name), and very short songs (at least one Napalm Death song is less than a second long.)
Notable Grindcore bands include: 
 
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