A casino, also known as a gambling hall or gaming house, is a building or room in which people can gamble and play games of chance. Most casinos feature table games such as blackjack and craps, but some also offer video poker, baccarat, and roulette. In the United States, about 51 million people—about a quarter of all adults over the age of 21—visited casinos in 2002. Casinos generate millions of dollars in profits, mostly from the vig (or “vigorish”) charged on bets.
Casinos also make money from non-gambling activities, such as restaurants, shows, and retail stores. In addition, they often earn money from the commission—called the rake—that they charge on some games. The rake is the amount that a casino takes out of each bet, and it can vary depending on the game rules.
Because of the large amounts of money that change hands, a casino is an environment where cheating and stealing are commonplace. Both patrons and employees may try to cheat or steal, either in collusion with others or independently. To counter these risks, most casinos employ a variety of security measures.
The most obvious security measure is the presence of surveillance cameras. In some casinos, these are located throughout the building, while in others they’re restricted to certain areas. Cameras are designed to capture any suspicious activity, and they can be adjusted by security personnel in a separate room filled with banks of monitors. In addition to video surveillance, casinos rely on sophisticated computer systems to supervise their games. In one example, betting chips have built-in microcircuitry that interacts with electronic systems in the tables to allow casinos to check the exact amounts being wagered minute by minute and to spot any statistical deviations.