Card counting is a skill which is used by gamblers of card games to achieve an edge by following cards which have been used. This gives the player a theory of the sum of cards, which have to be dealt with. Card counting is an ability that is more beneficial in vingt-et-un than in other card game.

In chemin de fer, a player is at an advantage when the remaining deck holds "big value cards." Big value cards should be faces and aces. The card counter in the gambling hall uses such situations by placing greater wagers, as and when they happen. Several skillful gamblers use the makeup of the deck to change their overall strategy. New gamblers occasionally have problems while engaged in quick card counting and may be prone to errors, when it comes to dealing with dealt decks. Twenty-one card counting is an industry by itself. millions and millions are made or spent, both by the players and the gambling dens, depending on card counting schemes in use.

Technology has made its impact on counting cards too, with improved computing power affecting the entire process. Traditional gamblers however vow that a card counting scheme of greater complexity is more prone to error, evening out the extra accuracy allowed by the use of technology. One can locate many game plans for 21 card counting by visiting online resources dedicated to vingt-et-un. With the game growing in popularity in casinos all over the planet, there are newer plans being developed every other day. One can locate at least hundreds of Web pages giving you hints on counting cards and the across the board strategy to earn money playing black jack.