A casino is a place where people can play games of chance. These establishments often offer a variety of entertainment options, including dining, theaters, and other events. Some casinos are operated by government agencies while others are private businesses. Many countries have legalized gambling, and the United States is the largest casino market.

A large number of casinos are located in hotels, resorts and other tourist destinations. Some are standalone facilities, while others are attached to other establishments such as restaurants, bars and nightclubs. The term casino may also refer to a specific type of game, such as roulette or blackjack. Some casinos specialize in one or more particular games, such as baccarat, craps, and sic bo.

In the United States, most land-based casinos are located in Atlantic City, New Jersey; Las Vegas, Nevada; and Reno, Nevada. In addition, a few Indian reservations have casinos. The popularity of casino gambling has caused some states to relax their antigambling laws. Casinos are also found in some cities in Canada, Japan, and South Korea.

The casinos make money by charging customers for food and drink, and through commissions on some games, such as poker. They also earn revenue from the rental of space for non-gambling events, such as weddings and meetings. Casinos have evolved into complex operations using advanced technology to control costs and maximize profits. For example, casino chips have built-in microcircuitry that enables them to be monitored minute by minute and alerted to any abnormalities; roulette wheels are electronically monitored regularly to discover statistical deviations quickly. Moreover, some casinos employ specialized mathematicians to calculate the house edge and variance for each of their games.