Professional gambler

Advantage gambling, or advantage play, refers to legal methods, in contrast to cheating in casinos, used to gain an advantage while gambling. The term usually refers to house-banked games, but can also refer to games played against other players, such as poker. Someone who practices advantage gambling is often referred to as an advantage player, or AP. Unlike cheating, which is by definition illegal, advantage play exploits innate characteristics of a particular game to give the player an advantage relative to the house or other players. While not illegal, advantage play is often discouraged and some advantage players may be banned from certain casinos.

A skillful or knowledgeable player can gain an advantage at a number of games. Card games have been beaten by card sharps for centuries. Blackjack and other table games can usually be beaten with card counting, hole carding, shuffle tracking, edge sorting, or several other methods. The players most skilled in these techniques have been nominated to the Blackjack Hall of Fame. Some video poker games, such as full pay Deuces Wild, can be beaten by the use of a strategy card devised by computer analysis of the game and often for sale in casino gift shops. And similar to the Blackjack Hall of Fame, there is an internet "Video Poker Hall of Fame". Some slot machines and lotteries with progressive jackpots can eventually have such a high jackpot that they offer a positive return or overlay when played long term. Some online games can be beaten with bonus hunting.

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Wikipedia