It is the famous waltz 'Waves of the Danube' composed by the Romanian Josef (or Ion) Ivanovici in 1880. This tune has been used in many films over the years – Josef von Sternberg’s Dishonored, Akira Kurosawa’s Stray Dog, and Emir Kusturica’s When Father Was Away on Business, to name a few – but its most famous film incarnation is as The Anniversary Song from The Jazz Singer(1927)
Raj Kapoor first heard this tune when he saw The Jolson Story (1946) rather than coming across a recording of the original waltz. He was so mesmerized by this tune, he decided to use this in his film Barsaat. When he used this tune in Barsaat, he was approached by the copyright people for breaching the copyright. He had to pay something like 35,000 rupees, a handsome amount in the 40s.
Since he purchased the tune, he used this tune in RK films – Jis Desh Mein Ganga Behti Hai (1960), Sangam (1964), Mera Naam Joker (1970), Bobby (1973), Biwi O Biwi (1982) – either as background music or in song interludes.
This tune remained an integral part of the film. Raj Kapoor, who plays Pran in the film plays this tune on the violin throughout the film. Nargis (Reshma), who keeps referring to the instrument as a “sitar”, finds herself inextricably drawn to this haunting melody. In a crucial scene towards the end, when the lovers have been separated, Reshma again hears the tune and rushes off towards its source. She lands up in a posh club (with, apparently, not very sound-proof walls) and falls at the feet of the man playing the violin. But it is not Pran. The shocked violinist kicks out at her.
