The Elf on the Shelf is a Christmas tradition that involves a special elf toy that is hidden in a different place each day leading up to Christmas. The elf is believed to be a scout sent from the North Pole to report back to Santa on children's behavior. Each day, the elf is placed in a new spot to give children a reason to explore and discover new areas of their home. The elf is not supposed to move when someone is watching, and children are told not to touch it or it will lose its magic.