Blackjack, also known as 21, is one of the easiest casino card games to learn. In the beginning of the game each player is given two cards by the dealer. Every number card is worth its face value, the face cards are worth 10, and the aces can be worth 11 or 1.
After that the dealer draws 2 cards, but only one is shown to the player. The face down card is sometimes call a hole card.
The goal is to not get 21 as the name of the game would suggest, but to beat the dealer who is required to keep drawing until he has at least 17, depending on the rules. Because of that sometimes you can win by having just 12, or 4 for that matter, when the dealer is overdrawn and has more than 21.
There is a way to play blackjack that gives the best odds without counting cards, it is called the basic blackjack strategy. You can download and print black jack strategy table and chart. To play it perfectly it's better to memorize it using blackjack strategy trainer.