Casino, also called simply a casino or a gambling hall, is an establishment where people can play games of chance or skill. Casinos vary in size from massive resorts to small card rooms. In the United States, casinos can be found in Las Vegas, Atlantic City, and on Indian reservations. They generate billions of dollars in annual profits for their owners, shareholders, and customers.

Casinos are regulated by state and local governments. They are also subject to rigorous security measures. In general, casino security begins with employees on the floor of a casino, who keep their eyes peeled for blatant cheating, such as palming, marking, or switching cards or dice. In table games, pit bosses and table managers have a broader view of the tables and patrons, keeping an eye out for betting patterns that suggest collusion or cheating.

To encourage gamblers to spend more money, casinos offer free goods and services, known as comps. These perks include food, hotel rooms, and tickets to shows. Players can also receive limo service and airline tickets if they play for long enough and bet large amounts.

The average casino gambler is a forty-six-year-old female from a household with an above-average income. In 2005, this demographic accounted for about two-thirds of the revenue generated by casino gambling. Addiction to gambling is a serious problem and can result in personal bankruptcy and family problems. Studies show that, on balance, casinos provide a negative economic impact on the communities where they operate. This is primarily because they draw away local spending on entertainment and other economic activities.