There are times I’ve watched a film (like Daag, or Pyaar ka Mausam, or Taqdeer) and got the distinct feeling that the music director composed one especially good tune in the film, and that was a fact acknowledged by the film maker too, who decided to use that tune in different versions throughout the film. Therefore we have Ae mere dil kahin aur chal in several versions, and the same with Tum bin jaaoon kahaan or Jab-jab bahaar aayi aur phool muskuraaye. The tune, at least in essence is the same (the tempo may change); the singer(s) may be different, the actors who lip-sync to it may be different, and there may be other differences as well.
‘Multiple version’ songs can be of different types. The most common (from what I can tell; I haven’t researched this) is the differentiation of tone: the happy version/sad version scenario. One version of the song (usually the one that appears earlier in the film) is an upbeat, happy one; the other uses the same tune, but often different lyrics that reflect two different situations.
Then there are songs where different versions may be only sung by different playback singers—which might include (as in the case of Jab-jab bahaar aayi) one version sung as a solo, another as a duet or even by a trio. There are also versions (overlapping with regional language cinema) where the same tune is used in songs in films of different languages, for instance the Bengali song Ei raat tomaar aamaar (from Deep Jwele Jaai) appears as the lovely Yeh nayan dare-dare in the Hindi film Kohraa.
Those are versions for other, later song lists. For this post, I’m going to confine myself to one particular type of ‘multiple version’ song: the solo male singer/female singer song.