The "pile shuffle" is a method used to randomize a deck of cards. In this technique, the deck is divided into several smaller piles, typically of equal size. Each pile is then stacked on top of one another, creating a new arrangement of the cards. This process helps to ensure that the cards are mixed thoroughly. This shuffling method is often used in card games to maintain fairness and unpredictability. While it may not be as efficient as other shuffling techniques, such as the riffle shuffle, it is simple and easy to perform, making it a popular choice for casual play.