Testament is an American thrash metal band from Berkeley, California. Formed in 1983 under the name Legacy, they are often credited as one of the most popular bands of the 1980s thrash metal scene. In the 31 years since its inception, Testament has had numerous lineup changes, and guitarist Eric Peterson has been the only constant member, although the band currently also features another one of its original members, Alex Skolnick (guitarist). Chuck Billy replaced former singer Steve Souza in 1986, prior to the recording of their first studio album, The Legacy, and has been a member of the band since.

To date, Testament has released ten studio albums, four live albums, six compilation albums, and six singles. After signing a recording contract with Atlantic Records in 1986, they released their debut album The Legacy in 1987 to critical acclaim. Many of their subsequent albums — The New Order (1988), Practice What You Preach (1989), Souls of Black (1990), The Ritual (1992) and The Formation of Damnation (2008) — were also successful. Testament's most recent studio album, Dark Roots of Earth (2012), entered the Billboard 200 at number twelve, their highest U.S. chart position so far. By July 2012, Testament had sold over 1.4 million albums in the U.S since the beginning of the SoundScan era.