Metalcore

Metalcore is a fusion genre incorporating elements of hardcore punk and extreme metal. The name is a portmanteau of heavy metal and hardcore punk. The term took on its current meaning in the mid-1990s, describing bands like Earth Crisis, Deadguy and Integrity. The earliest of these groups, Integrity, began performing in 1989. Metalcore is distinguished from other punk metal fusions by its emphasis on breakdowns: slower, intense passages conducive to moshing.

Source : http://en.wikipedia.org/wiki/Metalcore