How does the online card trick work?

How does the twenty-one card trick work?

• Answer:

  Here is how the 21 card trick works. The cards are dealt into the piles one at a time, like when dealing out hands in a card game. Each time they are dealt out, after the spectator indicates which pile contains the thought of card, the magician places that pile between the other two. After the first time, the card will be one of the ones in position 8-14. When the cards are dealt out the second time, the selection will be the third, fourth, or fifth card in the pile it ends up in.