If thinking about it then it gets obvious that when you play online blackjack, each known card changes the composition of the deck, ie affects the combinations that are more or less likely to appear. Winning or losing in blackjack, respectively, depends on the cards left in the deck.

Hence we need to have a card in blackjack, no excitement, and strict adherence to the basic strategy of the game in any casino. To know the composition of the deck is not necessarily to assume all the known cards, and it is not possible to do.

The main system of card counting blackjack strategy is to divide a deck of cards on the output of which is beneficial to the player and the cards profitable to the casinos. In a system of cards counting blackjack has lots of differences, but the scheme is the same.

In the system of card counting of Stanford Wong (some sources give the authorship Harvey Dubner) (High-Low) deck is divided into cards that would be beneficial to the player - 10, Jack, Queen, King, Ace, and cards, profitable to the casino - 2 3, 4, 5, 6. And those and other cards in the deck have an equal amount.

At the beginning of the game in blackjack account there is 0, exit cards, best casino, add 1, exit cards, best player, deduct from Account 1. Cards 7, 8, 9 are not counted. The lower the account comes to the "minus", the less favorable the deck and vice versa.