AC/DC are a hard rock band formed in Sydney, Australia in 1973 by brothers Angus and Malcolm Young. The band is considered a pioneer of hard rock and heavy metal, alongside bands such as Led Zeppelin, Deep Purple, and Black Sabbath. However, the members have always referred to their music as "rock 'n' roll".

AC/DC went through several line-up changes before releasing their first album, High Voltage in 1975. The membership remained stable until Cliff Williams replaced Mark Evans in 1978. In 1979, the band recorded their highly successful album Highway to Hell. Lead singer and co-songwriter, Bon Scott, died on February 19, 1980 after a night of heavy drinking. The band briefly considered breaking up, but decided to continue. They began holding auditions for a new lead singer and eventually recruited ex-Geordie singer Brian Johnson as Scott's replacement. Later that year, the band released their biggest-selling album, Back in Black.

The band's next album, For Those About to Rock We Salute You, was also highly successful and was the first hard rock album to reach #1 in the U.S. However, the band experienced a decline in popularity soon after the departure of drummer Phil Rudd in 1983. Poor record sales continued through the remainder of the decade. AC/DC regained much of their popularity in the 1990s with their album The Razor's Edge. Phil Rudd returned to the group in 1994 and contributed to the band's 1995 album Ballbreaker. Stiff Upper Lip was released in 2000 and was well-received by critics. A new album is expected in 2007.

The band has sold over 150 million albums worldwide, with over 68 million albums sold in the United States alone, making them one of the most successful hard rock bands. Back in Black has sold 42 million units worldwide, including 21 million in the U.S., making it the second highest-selling album of all time and the biggest-selling album by any band. The band are ranked number four on VH1's 100 Greatest Artists of Hard Rock.