Nu metal (sometimes stylized as nü-metal, with a metal umlaut) is a subgenre of alternative metal that combines elements of heavy metal music with elements of other music genres such as hip hop, funk, industrial, and grunge. Nu metal rarely features guitar solos or other displays of musical technique and emphasizes rhythm with instrumentation that is heavily syncopated. Nu metal guitarists often use seven-string guitars that are down-tuned to produce a heavier sound. Vocal styles are often rhythmic and influenced by hip hop, and include singing, rapping, screaming and sometimes growling. DJs are occasionally featured to provide instrumentation such as sampling, turntable scratching and electronic background music. Nu metal is one of the key genres of the new wave of American heavy metal.
In the late 1980s and early 1990s, bands like Pantera, Helmet, and Faith No More were influential in the development of nu-metal with their groove metal and alternative metal styles. Korn is often credited as pioneering the subgenre in the mid-1990s with their self-titled debut album. Nu metal became popular in the late 1990s, with bands and artists such as Korn, Limp Bizkit, and Slipknot all releasing albums that sold millions of copies.