Metallica is an extremely successful American thrash metal band that has been active since the early 1980s. The band has sold over 200 million albums worldwide, making them the most successful heavy metal act in history.

After building a following through its role in the development of thrash metal in the 1980s, the band successfully broadened its audience in the early 1990s to include many new fans.

      Accordingly, the band stood as the most commercially visible example of the metal genre for most of that decade. In contrast, Metallica's vastly increased commercial success was accompanied by stylistic changes that fostered accusations of "selling out" by some long-time fans though picking up many new fans.

Metallica's For Whom the Bell Tolls