AC/DC are an Australian rock band, formed in 1973 by brothers Malcolm
and Angus Young, who have remained the sole constant members. Commonly
classified as hard rock, they are considered pioneers of heavy metal and are
sometimes classified as such, though they themselves have always classified
their music as simply "rock and roll". To date they are one of the highest
grossing bands of all time.

AC/DC underwent several line-up changes before releasing their first album,
High Voltage, on 17 February 1975. Membership subsequently stabilised until
bassist Mark Evans was replaced by Cliff Williams in 1977 for the album
Powerage. Within months of recording the album Highway to Hell, lead singer
and co-songwriter Bon Scott died on 19 February 1980, after a night of heavy
alcohol consumption. The group briefly considered disbanding, but Scott's
parents urged them to continue and hire a new vocalist. Ex-Geordie singer
Brian Johnson was auditioned and selected to replace Scott. Later that year,
the band released their highest selling album, and ultimately the third
highest-selling album by any artist, Back in Black.