Blue is used on black in cartoons for the hair. It helps to add texture to the hair and show which way it flows. You know how in cartoons they're outlined in black? And they use black lines in hair to show the wavyness and so forth? Well, you can't use black on black, right? You coulnd't see it. So... they use blue instead.\n\nYoure shoes are the huge ones clowns wear that are red, or they're your pink, fuzzy, bunny slippers.