Half of the musical is song, the other half is dance, hence the name.
The "Song" half is about a nameless women and her romantic trials. She moves from England to Manhatten and has to deal with American relationships.
The "Dance" part is dances set to "Variations", instrumental segments of music created by Andrew Lloyd Webber.
Original Actors and Actresses
Andrew Lloyd Webber wrote Variations for his brother, Julian, because of a bet he lost against a soccer team in England. Julian won, so Andrew wrote Variations.
"Song and Dance" Links