Casino card games don't come more exciting or simple to understand than Blackjack. Since its introduction to land-based casinos in the twentieth century, the. Blackjack is a simple game, but there are a lot of details among the rules. Select online play if you want to learn how to play blackjack at an online casino. Different casinos have different casino rules and variations in Blackjack. Knowing the variations are important because they affect chances of winning.