Heavy metal, a genre of rock music that was hugely popular in the United States and much of the world during the 1980s, not only left an influence on successive trends in rock music, but affected the cultural tastes and style of its many fans. The heavy metal sound was characterized by loud and distorted guitars and vocals; its image by aggressive male posturing and a preoccupation with sexuality, identity, and the corrosion of traditional social institutions. While sometimes causing controversy, even outrage among the establishment for its perceived negative influence on youth, heavy metal expanded the range of recognized images and sounds in rock 'n' roll, developing a formula that combined musical virtuosity with social rebellion. While the groups achieved little Top 40 success even at the height of the genre's popularity, their albums and concerts outsold all their contemporaries, and outlasted them in influence.

Historically...