Metallica – Best Classic Rock Artists A-Z

Back in the '80s, when hard rock and metal in their purest forms were on life support, the mighty Metallica breathed new life into a genre that probably wouldn't have made it too far into the next millennium without them.

Metallica were fierce, brutal and aggressive on classic albums like 1986's milestone 'Master of Puppets.' or their 1983 debut, the charmingly titled 'Kill 'Em All.' Their self-titled 1991 album set the tone for the decade's hard-rock bands. But they could also be softer and reveal a more vulnerable side -- something you didn't see too much in guitar-powered hard rock bands before or even after them.