Considering that most casinos now use four or more decks of cards for a Blackjack game you'd have to be really sharp to be able to keep track of at least 208 cards. The only thing that card counting could do in such a case would be to give you an idea as to how many big or small cards are left in the shoe, which in turn could help you decide whether to take a hit or not. Just don't get caught, casinos do not like card counters.
Chat with our AI personalities
The advantage of counting cards in a blackjack card game is that it allows you to determine the probability of the cards in the next hand will give you or the dealer an advantage. It helps the player keep a running tally of all high and low value cards.
There have been many books written by gamblers and mathematicians that describe methods and tips for counting cards while playing blackjack. Gambling websites such as Wizard of Odds, Blackjack Authority, and Blackjack Tactics also have articles about card counting systems. It is worth noting that many casinos will eject players that they detect counting cards.