A casino is an establishment for gambling. Some casinos are combined with hotels, resorts, restaurants, retail shops or cruise ships. They may also host live entertainment events such as concerts and sports competitions. In the United States, casinos are usually located in urban areas and are often designed with a distinct architecture. Several states have legalized casino gambling, with Las Vegas being the best known destination for tourists and high rollers. Others, such as Iowa and Native American reservations, are not bound by state antigambling laws.

Casinos have many security measures in place to deter cheating and theft. They use cameras, and they employ special personnel to oversee table games, especially poker rooms. Some casino security staff have been trained to spot blatant cheating, such as palming or marking cards. Casinos also monitor games with computer systems, to ensure that bets are made in the correct amount minute by minute and to discover any statistical deviation from expected results quickly.

Some studies suggest that the net effect of casinos on a community is negative, because they shift money from other forms of local entertainment and can increase crime rates. They may also hurt property values in their immediate area. Critics point out that compulsive gamblers can generate a disproportionate share of casino profits, and that the cost of treating problem gambling and the lost productivity of those who cannot control their spending offsets any economic benefits that a casino might bring.