"Refrain" was the winning song of the Eurovision Song Contest 1956, co-written by Émile Gardaz and Géo Voumard, performed by Lys Assia representing Switzerland. It was the first-ever winner of the Contest, but not the first-ever performance by Switzerland. This apparent anomaly is due to the rules of the 1956 Contest allowing (for the only time to date) each competing country to be represented by two songs. Assia represented Switzerland singing both songs (one of only two performers to do this), and had previously performed "Das alte Karussell" in German ("Refrain" was sung in French).
The song is in the classic chanson mode and laments the lost loves of the singer's "adolescence" (the French original reads "vingt ans", which can also be rendered "twenties" in English).