A subgenre of rock music known as heavy metal (or just metal) emerged in the late 1960s and early 1970s, primarily in the United Kingdom and the United States, and has since spread worldwide. Heavy metal bands created a thick, massive sound that was influenced by blues rock, psychedelic rock, and acid rock. Distortion, lengthy guitar solos, forceful rhythms, and loudness were all characteristics of this sound. The songs and performances are often linked with anger and machismo, which has led to charges of sexism on the part of some women who watch the show.
In 1968, three of the most well-known pioneers of the genre, Led Zeppelin, Black Sabbath, and Deep Purple, were formed in the United Kingdom. Despite the fact that they gained widespread popularity, they were often ridiculed by critics. Several American bands transformed heavy metal into more accessible forms during the 1970s: the raw, sleazy sound and shock rock of Alice Cooper and Kiss; the blues-based rock of Aerosmith; and the vibrant guitar leads as well as party rock of Van Halen. Alice Cooper and Kiss were among the bands who modified heavy metal into more accessible forms. Midway through the decade, Judas Priest contributed to the development of the genre by rejecting most of its blues influence, while Motörhead injected a punk rock sensibility and a growing focus on speed to the mix, respectively. Beginning in the late 1970s, bands associated with the new wave of British heavy metal, such as Iron Maiden and Saxon, continued in a similar vein to their predecessors. Heavily metal fans were recognised by the end of the decade as "metalheads" or "headbangers," respectively.
Glam metal became popular in the 1980s, thanks to the likes of Bon Jovi and Mötley Crüe, among other bands. As a result of this, underground scenes gave rise to a diverse range of more aggressive styles: thrash metal, which gained popularity with bands such as Metallica, Slayer, Megadeth, and Anthrax, and other extreme subgenres such as death metal and black metal continue to exist as subcultures. Since the mid-1990s, popular styles have pushed the boundaries of what constitutes a genre. Groove metal and nu metal are examples of this, with the latter incorporating elements of grunge and hip hop into its composition.