A casino is a facility where people can gamble and play games of chance. These establishments are sometimes known as gaming houses or gambling dens, and they typically offer a variety of games such as roulette, blackjack, poker and slot machines. Many casinos also feature entertainment such as concerts and shows. Casinos are usually located in tourist destinations or in areas with high concentrations of people who enjoy gambling. They can also be found in some military bases and Native American reservations.

Something about the large amounts of money that casinos handle encourages cheating and stealing, either in collusion or by individual patrons. That is why most casinos spend a significant amount of time and money on security. Cameras located throughout the casino watch every table and doorway, and elaborate surveillance systems can zoom in on suspicious patrons from a room filled with banks of monitors. Windows and clocks are rarely seen in casino gambling halls, to prevent players from calculating how long they have been playing (and spending) money.

While some of the earliest casinos were run by organized crime groups, mob control faded as real estate developers and hotel chains realized the profits they could make from running casino properties. In addition, federal crackdowns and the risk of losing a casino license at even the slightest hint of Mafia involvement have kept mob influence out of modern casinos. Nevertheless, some economists contend that casinos do more harm than good to the economy of a region because they shift spending from other forms of local entertainment and cause compulsive gamblers to waste resources that would otherwise be invested in productive activities.