Jason Newsted is an American musician best known as the bassist for the heavy metal band Metallica. He joined the band in 1986, contributing to several of their most famous albums, including And Justice for All and Metallica, often referred to as the "Black Album." Newsted's energetic playing style and vocal contributions helped shape the band's sound during his tenure. In 2001, Newsted left Metallica due to personal reasons and a desire to explore other musical projects. He later formed the band Echobrain and played with Ozzy Osbourne and Voivod. Newsted's influence on heavy metal music remains significant, and he is respected for his contributions to the genre.