As mentioned above, the aim of card counting in blackjack is to track the ratio of high cards to low cards in the deck of cards. The reason for this is that a high proportion of high cards to low cards is positive for the players, while a higher proportion of low cards to high cards is positive for the dealer.

A deck that has a high proportion of high cards (in other words, many tens and Aces) is considered good for the player as it makes achieving blackjack more likely. It also means that the dealer is more likely to bust on a stiff hand. A dealer must always hit up until a soft 17, so if he holds 16 points and the deck is full of 10s, his chances of going bust are increased. Double downs also become more successful in a deck that has a high proportion of high cards.

If a player knows that there are more high cards to low cards in the deck and therefore there is more chance of a blackjack occurring, he can increase his bet. As blackjack pays out at 3 to 2, in the long run, they will win more. On the other hand, when the deck contains more low cards than high cards and therefore favors the casino, it would be wise to decrease your bet.

Contrary to popular belief, when card counting in blackjack, you do not have to memorize every card that has come before. This would be virtually impossible particularly when playing blackjack games that use a large number of decks. Rather, an indicator number is assigned to every card and then the total score is kept. The total score that is tracked is referred to as the count.

There are a number of different card counting strategies in blackjack and they all have their advantages and disadvantages. It is most important for you to find a system that is the easiest system for you to remember as this will reduce the chances of you making mistakes. Mistakes can be very costly when you are counting cards in blackjack.

As card counting increases the player's odds, many casinos attempt to prevent players from counting cards. This may be as simple as engaging them in conversation to attempt to break their concentration. Casinos may shuffle the decks more often or shuffle whenever a suspected card counter increases their bet. This affects the casino's winnings as well, however as it reduces the time that non-card counting players are playing and therefore decreases the casino's takings.