"High-Low-Jack" is a popular casino card game that involves players betting on the highest or lowest card in a shuffled deck. The game is also known by various synonyms, including "Hi-Lo," "High or Low," "Elevens," and "Switch." In some regions, the game is referred to as "Acey-Deucey," "Slapjack," or "Blackjack Switch." These synonyms reflect slight variations in the rules or playing style but essentially offer the same thrilling experience of predicting card outcomes. Whether played for fun or real money, "High-Low-Jack" and its synonyms have remained a staple in the world of card games.