A casino is a place where people gamble by playing games of chance or skill. Some casinos specialize in specific types of gambling such as poker, blackjack or roulette. Others offer more general gambling such as slot machines or craps. In the United States, about 51 million people, or one quarter of the adults over 21, visited a casino in 2002. Most of them went to Las Vegas, which is the best-known casino city in the world. Casinos use a variety of incentives to keep regular gamblers coming back. These include floor shows, free drinks and all-you-can-eat buffets. Some casinos also give players comps, or complimentary items, based on how much they spend.
In table games such as poker, the house takes a percentage of all bets placed, called the rake. This is in addition to any money won by the player. In slots and other machine-based games, the house has a built-in advantage over the gamblers that can be expressed mathematically as the “house edge.”
The most popular casino game is the slot machine, which earns casinos a larger share of their profits than any other activity. Players put in money and pull a handle or push a button to spin reels containing varying bands of colored shapes; if the right pattern comes up, the player wins a predetermined amount of money. Slots are generally automated, so there is no need for a live dealer.
Many other casino games are played with a live croupier, but the house still has an advantage. Craps, for example, has a higher house edge than roulette. To offset this, some casinos reduce the table’s minimum bet to entice small bettors. Casinos can also adjust the odds of winning or losing on each game to produce a desired profit margin.
To ensure that their customers are treated fairly, casinos hire mathematicians and computer programmers who study the game algorithms to discover any statistical deviations from expected results. The experts are known as gaming mathematicians or gaming analysts. They may be employed by the casino as employees or they may work independently for consulting firms.
Despite their profitability, casinos have been criticized for their negative economic impact on the communities they serve. For instance, the influx of gamblers from out-of-town can shift spending away from other local entertainment venues. Additionally, the cost of treating compulsive gamblers can exceed any profits the casino makes. Moreover, the casinos have been accused of lowering property values in surrounding neighborhoods. This negative effect, combined with the loss of tax revenue from gambling, can cancel out any benefits a casino might provide. As a result, some governments have banned or restricted the operation of casinos.