Metallica is an American metal band formed in Los Angeles in the early 1980s around James Hetfield and Lars Ulrich, later joined notably by Kirk Hammett and Cliff Burton. The group became known for a powerful sound blending thrash metal, heavy metal and increasingly ambitious compositions, driven by sharp riffs, precise rhythms and often dark songwriting. With albums such as Ride the Lightning, Master of Puppets, ...And Justice for All and Metallica, the band became one of the most influential and popular acts in metal history.