January 21st

Pick a Card, Any Card

A classic of card magic. The magician offers the cards to a spectator and asks for a selection to be made. After noting their card, the spectator is invited to return the card to the deck. The magician then goes through the pack and is able to easily divine the identity of the selection.

Explanation: 

Before the trick begins, separate the cards into red and black halves. When the spectator selects his card, note whether or not his selection comes from the red or black portion of the deck. If they’ve selected a red card, when the spectator places their card back in the deck, make sure they return their card to the black half. The opposite applies if the selection is a black card. It’s now easy to figure out what the selection is; simply go through the pack and find the card in the wrong group.