The group was formed in Sydney, Australia in 1973.
Born in Scotland, the brothers Angus and Malcolm Young moved with their family to Australia as children. Malcolm began playing guitar first, soon followed by Angus. Malcolm first played with a band called "The Velvet Underground" (not the Lou Reed group). Their older brother George had some success with his band The Easybeats, and asked the boys to do some session work for a project he was doing. Angus then formed a band called "Tantrum". After The Velvet Underground, Malcolm decided to form a more pure rock and roll band, and enlisted Angus.
The name "AC/DC" (alternating current/direct current) was suggested by their sister Margaret after she read it on a vacuum cleaner label. The term has a bisexual connotation that they were apparently unaware of, and they often had to deny they were a gay band.
The early lineups were changed often, but the enlistment of their driver Ronald "Bon" Scott as frontman signified the beginning of real success. Upon his death in 1980 after choking on his own vomit after a night of hard drinking, the band brought in singer Brian Johnson, and released their biggest-selling album to date, the hard-rock landmark "Back in Black", named in tribute to Bon.
AC/DC is generally divided into "Bon Scott era (1975-80)" and "Brian Johnson era (1980-present)". Some fans have a preference, but die-hard devotees point to the merits of both singers and love them equally.