The use of the term "jack" to refer to the playing card comes from the original French word "valet," which means "servant" or "attendant." In the original French deck, the "valet" represented a royal servant or a courtier.
Blackjack is a classic casino card game, also referred to as 21. The object of the game is simple get your hand total to score as close to 21 as possible, without exceeding 21. There's no greater feeling for a player than getting a natural blackjack!