Metalcore is a fusion genre that incorporates elements of the hardcore punk and heavy metal genres. The term is a portmanteau of heavy metal and hardcore punk. Metalcore emphasizes breakdowns, and sometimes discards the conceptual trappings of both its parent genres. Modern metalcore is typically melodic.

Through the 1990s, metalcore was mostly an underground phenomenon, but from roughly 2004 to the present, many bands have appeared on the Billboard album charts.

During to the rise in popularity of heavy metal in the early 2000s, also many metalcore bands influenced the New Wave of American Heavy Metal.