Metalcore (or metallic hardcore) is a fusion music genre that combines elements of extreme metal and hardcore punk. As with other styles blending metal and hardcore, such as crust punk and grindcore, metalcore is noted for its use of breakdowns, slow, intense passages conducive to moshing. Other defining instrumental qualities include heavy riffs and stop-start rhythm guitar playing, occasional blast beats, and double bass drumming. Vocalists in the genre typically yell or scream. Some later metalcore bands combine this with clean singing, often during the chorus. Death growls and gang vocals are common. 1990s metalcore bands were inspired by hardcore while later metalcore bands were inspired by melodic death metal. Melodic death metal bands like At the Gates and In Flames influenced later metalcore bands. The roots of metalcore are in the 1980s when bands would combine hardcore punk with heavy metal. This included New York hardcore bands like Agnostic Front, Cro-Mags, and Killing Time, British hardcore punk bands like The Exploited and Discharge, and American crossover thrash bands like Dirty Rotten Imbeciles and Suicidal Tendencies. The genre emerged in the early 1990s and expanded in the mid–late 1990s. Metalcore bands like Integrity, Earth Crisis, Hatebreed, Converge, Shai Hulud, Vision of Disorder, Merauder, and Disembodied emerged and acquired underground success in the 1990s. In the mid-2000s, metalcore became one of the most popular heavy metal subgenres with the success of bands like Bleeding Through, Avenged Sevenfold, Killswitch Engage, Hatebreed, Atreyu, Shadows Fall, As I Lay Dying, Unearth, Trivium, Bullet for My Valentine, and All That Remains. Metalcore's popularity continued in the 2010s with the success of bands like Asking Alexandria, August Burns Red, and The Devil Wears Prada. Metalcore subgenres like deathcore, easycore and electronicore also emerged in the 2000s decade. Other subgenres of metalcore include mathcore, nu metalcore, melodic metalcore and progressive metalcore.