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ABBA (Swedish pronunciation: [2ab:a]) were a Swedish pop group, formed in Stockholm in 1972 by Agnetha Faltskog, Bjorn Ulvaeus, Benny Andersson, and Anni-Frid Lyngstad: the group name derives from the first letter in each of their names. They became one of the most commercially successful acts in the history of popular music, topping the charts worldwide from 1974 to 1982. ABBA won the Eurovision Song Contest 1974 at The Dome in Brighton, UK, giving Sweden its first triumph in the contest. They are the most successful group to have taken part in the competition.

As the group entered the Melodifestivalen with "Ring Ring" but failed to qualify as the 1973 Swedish entry, Stig Anderson immediately started planning for the 1974 contest.  Ulvaeus, Andersson and Stig Anderson believed in the possibilities of using the Eurovision Song Contest as a way to make the music business aware of them as songwriters, as well as the band itself. In late 1973, they were invited by Swedish television to contribute a song for the Melodifestivalen 1974 and from a number of new songs, the upbeat song "Waterloo" was chosen; the group was now inspired by the growing glam rock scene in England.  ABBA won their national heats on Swedish television on 9 February 1974, and with this third attempt were far more experienced and better prepared for the Eurovision Song Contest. Winning the 1974 Contest on 6 April 1974 gave ABBA the chance to tour Europe and perform on major television shows; thus the band saw the "Waterloo" single chart in many European countries. "Waterloo" was ABBA's first number-one single in big markets such as the UK and West Germany. In the United States, the song peaked at number-six on the Billboard Hot 100 chart, paving the way for their first album and their first trip as a group there. Albeit a short promotional visit, it included their first performance on American television, The Mike Douglas Show. The album Waterloo only peaked at number 145 on the Billboard 200 chart, but received unanimous high praise from the US critics: Los Angeles Times called it "a compelling and fascinating debut album that captures the spirit of mainstream pop quite effectively ... an immensely enjoyable and pleasant project", while Creem characterised it as "a perfect blend of exceptional, lovable compositions".  ABBA's follow-up single, "Honey, Honey", peaked at number 27 on the US Billboard Hot 100, and was a number-two hit in West Germany. However, in the United Kingdom, ABBA's British record label, Epic, decided to re-release a remixed version of "Ring Ring" instead of "Honey, Honey", and a cover version of the latter by Sweet Dreams peaked at number 10. Both records debuted on the UK chart within one week of each other. "Ring Ring" failed to reach the Top 30 in the United Kingdom, increasing growing speculation that the group was simply a Eurovision one-hit wonder.
ABBA