How to Understand the secret behind vanishing tricks

In this video from Socoolscienceshow, Crazy Chris explains to us how magicians make things disappear. For this he uses a plate, cup, and a napkin. You cover the cup and plate with a napkin. He removes the napkin with the cup and shows that he taped the cup to the bottom of the plate so they are both removed at the same time. To maintain the look of the cup in that napkin when it's removed he shows that he trace the cup onto some construction paper cut it out, and tape it to the napkin. Then he goes on to explain this in a more scientific manner. Viewers of this will understand a magician's secret!