Counting cards is a technique that is employed by gamblers of card games to achieve an edge by tracking cards that have been played. This gives the player a theory of the importance of cards, that have to be dealt with. Card counting is a skill that is more useful in 21 than in other card game.

In black jack, a gambler has an advantage when the remaining shoe contains "high cards." High cards should be faces and aces. The counter in the casino takes advantage of these opportunities by laying bigger wagers, as and when they occur. A great many adept players use the composition of the deck to alter their overall tactic. Inexperienced players at times experience problems while engaged in fast counting and might be subject to mistakes, when it comes to working with dealt cards. Blackjack card counting is an enterprise on its own. Millions are won or squandered, both by the gamblers and the casinos, depending on card counting strategies in use.

Technology has made its impact on card counting too, with improved computing power affecting the complete process. Long-established gamblers however swear that a card counting scheme of greater complexity is more subject to problems, negating the extra accuracy permitted by the use of technology. Anyone can find many plans for 21 card counting by going online sites devoted to the game. With the game growing in popularity in gambling halls around the world, there are newer game plans being created every other day. One can find beyond a doubt hundreds of internet sites giving you pointers on counting cards and the overall tactic to make money through 21.