AC/DC are an Australian rock band formed in 1973. They were founded by brothers Malcolm Young on rhythm guitar and Angus Young on lead guitar. Their current line-up comprises Angus, bassist Cliff Williams, drummer Phil Rudd, lead vocalist Brian Johnson and rhythm guitarist Stevie Young – nephew of Angus and Malcolm. Their music has been variously described as hard rock, blues rock and heavy metal, but the band calls it simply "rock and roll". They are cited as a formative influence on the new wave of British heavy metal bands, such as Iron Maiden and Saxon. AC/DC were inducted into the Rock and Roll Hall of Fame in 2003.
AC/DC underwent several line-up changes before releasing their debut album, High Voltage (1975), which was not released outside of Australia. Membership subsequently stabilised after the release of Let There Be Rock (1977), with the Young brothers, Rudd, Williams and Bon Scott on lead vocals. Seven months after the release of Highway to Hell (1979), Scott died of alcohol poisoning and the other members considered disbanding. However, at the request of Scott's parents, they continued together and recruited English-born singer Johnson as their new front man. Their first album with Johnson, Back in Black (1980), was dedicated to Scott's memory. It became the second best-selling album of all time.
The band's eighth studio album, For Those About to Rock (1981), was their first album to reach number one in the Billboard 200. Prior to the release of Flick of the Switch (1983), Rudd left AC/DC and was replaced by Simon Wright, who was himself replaced by Chris Slade six years later. AC/DC experienced a commercial resurgence in the early 1990s with the release of The Razors Edge (1990); it was their only record to feature Slade, as Rudd returned in 1994. Rudd has since recorded five more albums with the band, starting with Ballbreaker (1995). Their fifteenth studio album, Black Ice was the second-highest-selling record of 2008 and their biggest chart hit since For Those About to Rock, eventually reaching number one worldwide.
The band's line-up remained the same for 20 years until 2014, when Malcolm retired due to early-onset dementia, from which he died three years later; additionally, Rudd was involved in legal troubles. Stevie, who replaced Malcolm, debuted on the album Rock or Bust (2014). On the accompanying tour, Slade filled in for Rudd. In 2016, Johnson was advised to stop touring due to worsening hearing loss and Guns N' Roses singer Axl Rose stepped in as the band's front man for the remainder of that year's dates. Long-time bassist Williams retired at the end of the tour in 2016 and the band entered a two-year hiatus. A reunion of the Rock or Bust line-up was announced in September 2020; the band's seventeenth studio album Power Up was released two months later. American drummer Matt Laug filled in for Rudd at the Power Trip festival in October 2023.