With hits such as "Dancing Queen," ABBA became synonymous with the disco trend of the 1970s. The Swedish pop group formed in Stockholm in 1972, though the musical partnership of Benny Andersson (vocals, keyboard) and Bjorn Ulvaeus (vocals, guitar) dates back to 1966. With the eventual addition of two female vocalists in Agnetha Faltskog and Anni-Frid Lyngstad, ABBA was officially formed, taking its name from an acronym of the members' first names. The debut single, 1973's "Waterloo," won the Swedish Eurovision song contest, sparking the group's career. In the following years, pop music fans worldwide would come to fall for ABBA's harmony-rich songs full of lavish production values and sunny melodies. The disco period helped the group hit its strongest stride, as the genre's characteristic beat and dance-friendly style matched its overall tone extremely well. Though some listeners will certainly find ABBA's music overly kitschy, the group's success and influence on pop music cannot be understated.