Card Counting Theory
Card counting has been in use since decades, but it got much publicity recently when the movie '21' was released. MIT blackjack team's play had been based on card counting techniques, so we can talk here about MIT card counting.
Card counting is a strategy used to determine when the player has advantage at the game. Card counting is used mainly in blackjack and its other forms like Spanish 21.
How It All Began
With the card counting theory, players can determine their probability ratios of their advantages and disadvantages during the game. Using this they can then determine whether to play or not and how much to bid which increases their levels of earning.
When players use only basic strategy in blackjack, even if it is perfect, they only have an edge of around 0.5%. A player who uses card counting techniques and uses it to his advantage will have an advantage of 1% approximately against the casinos. It is even possible to have an advantage of around 2.5% in certain games like Spanish 21.
However, this would depend on the skill levels of the player as well as various other factors like the penetration level, number of hands played per hour and several others. Blackjack has a high level of variance so even those who are skilled card counters would generally have to put in hours of play for making a sizeable amount of profit.
Also, the amount of profit generated by a card counter would also depend on the average bets he makes. If a player having a 1% advantage makes an average $50 bet then he would win around $0.5 per hand. This would mean that if he plays 50 hands every hour he would win $25. If he bets more he would win more.
A player who uses card counting techniques would generally try to increase the levels of profits by betting more. This would mean that a card counter would need a sizeable bankroll to make most of it. By calculating the odds of winning the player can then make the most of it by betting large amounts on hands where he/she has a higher probability of winning and not betting on hands where there is low probability of winning.
In the earlier days, card counting used to be done with the mind solely. Individuals good at math and those with a knack of quick calculations in the mind used to have an edge over the other. In the recent years, with the advancement in technology, there are plenty of devices available, which are used for card counting.
However, using devices for card counting is illegal in all casinos. Devices like applications for iPhones and other hand held devices were declared to be illegal for card counting by the Nevada Gaming Control Board in 2009. However, counting with your mind is still legal and according to many serious card counters it is even more effective.