it's sort of like those cleaners they used to have for cleaning the heads on a VHS player (same idea) I think it probably cleans the lens of the laser that reads the discs.
CORRECTION After reading on the pkg it looks like it's for cleaning the discs themselves. You spray the solution directly on the discs you are going to play. will post another picture with the directions to clear up any confusion of how it is used. I'm assuming that it comes with the cleaning cloth.