A casino is a facility where gambling takes place. The term is also used for a group of gaming rooms. In the United States, the largest casinos are located in Las Vegas and Atlantic City. Several other cities have smaller casinos. These casinos usually offer a variety of games, including slot machines and table games. They may also have restaurants and bars.

Security is a major concern for casinos. Both patrons and staff may be tempted to cheat or steal, either in collusion or independently; therefore casinos employ a number of techniques to prevent such activities. Video cameras and other technological devices monitor the casino floor for blatantly obvious cheating, such as palming, marking or switching cards, and roulette wheels are electronically monitored to discover any deviation from expected results. Many casinos use “chip tracking,” where betting chips have built-in microcircuitry that interacts with the gaming system to enable the casino to oversee the exact amounts being wagered minute by minute.

Casinos make money by charging a small percentage of every bet placed, called the house edge. This advantage can be as low as two percent, depending on the game. In addition to this, casinos generate additional income from the sale of food and drinks and from the rental of hotel rooms and suites. This revenue allows casinos to build elaborate structures such as fountains, pyramids, towers and replicas of famous landmarks. However, critics assert that the cost of treating compulsive gamblers and the loss of productivity caused by gambling addicts offset any economic benefits a casino might bring to a community.