ABBA are a Swedish pop group formed in Stockholm in 1972 by Agnetha Fältskog, Björn Ulvaeus, Benny Andersson, and Anni-Frid Lyngstad. The group's name is an acronym of the first letters of their first names arranged in a chiastic pattern. Widely considered one of the greatest musical groups of all time, they became one of the most commercially successful acts in the history of popular music, topping the charts worldwide from 1974 to 1983, and have achieved 48 hit singles.
In 1974, ABBA were Sweden's first winner of the Eurovision Song Contest with the song "Waterloo", which in 2005 was chosen as the best song in the competition's history as part of the 50th anniversary celebration of the contest. During the band's main active years, it consisted of two married couples: Fältskog and Ulvaeus, and Lyngstad and Andersson. With the increase of their popularity, their personal lives suffered, which eventually resulted in the collapse of both marriages. The relationship changes were reflected in the group's music, with latter compositions featuring darker and more introspective lyrics. After ABBA separated in December 1982, Andersson and Ulvaeus continued their success writing music for multiple audiences including stage, musicals and movies, while Fältskog and Lyngstad pursued solo careers.
Ten years after the group broke up, a compilation, ABBA Gold, was released, becoming a worldwide best-seller. In 1999, ABBA's music was adapted into Mamma Mia!, a successful musical that toured worldwide. A film of the same name, released in 2008, became the highest-grossing film in the United Kingdom that year. A sequel, Mamma Mia! Here We Go Again, was released in 2018.
In 2016, the group reunited and started working on a digital avatar concert tour. Newly recorded songs were announced in 2018. Voyage, their first new album in 40 years, was released on November 5, 2021.A concert residency featuring ABBA as virtual avatars - dubbed 'ABBAtars' - will take place in London from May to October 2022.