Blackjack Systems and Card Counting. The Hi-Low System.
Card counting is a playing technique that works favorably for most card games, and is not exactly loved by the casinos. Card counting is partially responsible for making Blackjack the popular casino game that it is today, as more players enjoyed success at the Blackjack tables.
The theory behind card counting is that, by using a consistent system to predict which cards are likely to be in the shoe, a player knows if the deck is in favourable or infavourable position for the player during the game, and bet accordingly. Unfortunately, card counting will not work for online Blackjack games, since the deck is reshuffed after each hand.
Card Counting was originally developed by Edward O. Thorp, a Mathematics Professor at New Mexico State University. In 1962 Thorp published "Beat the Dealer", which made its way to the New York Times bestseller list in 1963.
One popular card counting system is the "High-Low" system. This system keeps track of the availability of low cards (value 2 to 8) versus high cards (9 through Aces). A shortage of high cards the deck is unfavorable. The player keeps track of what cards are played and, if there are many high cards remaining (favorable), he/she will increase the size of the bets.
To keep track of the "value" of the remaining cards in the deck, the player assigns values to the cards as they are played. A low card counts as +1, and high card as -1, and middling cards (7 - 9) are not counted at all.