Metalcore is a subgenre of heavy metal music that combines elements of heavy metal and hardcore punk. It emerged in the early 1980s, and gained popularity in the 1990s and early 2000s.
Metalcore typically features fast, intense guitar riffs, breakdowns, and screaming vocals. The lyrics often deal with personal and social issues such as politics, mental health, and relationships. The style is characterized by a mix of clean singing and growling/screaming vocals, often done by two different singers.
Some of the key bands and artists that are considered pioneers of the metalcore genre are Killswitch Engage, As I Lay Dying, Unearth, Shadows Fall, and At the Gates. Metalcore is considered as a fusion of Heavy Metal and Hardcore Punk, which makes it a very intense and dynamic genre.
In recent years, metalcore has evolved and diversified, with many subgenres and variations emerging. Some popular subgenres include melodic metalcore, deathcore, mathcore and post-metalcore.