It was featured in the 1955 film Pete Kelly's Blues, where it was sung by Peggy Lee.
The song has been used to teach children names of colours.
[1][2] Despite the name of the song, two of the seven colours mentioned ("red and yellow and pink and green, purple and orange and blue") – pink and purple – are not actually a colour of the rainbow (i.e. they are not spectral colors; pink is a variation of shade, and purple is the human brain's interpretation of mixed red/blue [see line of purples]).
They are also not presented in order of the visible light spectrum.
Other version include: Red and yellow and pink and green Orange and purple and blue, I can sing a rainbow, Sing a rainbow, Sing a rainbow too.