A casino is an establishment that offers various forms of gambling. Casinos can also offer other types of entertainment and amenities such as restaurants, bars, and nightclubs. These establishments can be found in many cities and countries around the world. Some are owned by large corporations while others are operated by local governments. The casino industry is a source of employment for thousands of people worldwide.

The most well-known casinos are in Las Vegas, Nevada; Atlantic City, New Jersey; and Chicago, Illinois. Many of these casinos are located on American Indian reservations and are exempt from state antigambling laws. Some states have legalized casinos on riverboats or in other remote locations. In the United States, there are over 1,000 casinos.

Casino games are classified into three general categories: gaming machines, table games, and random number games. Gaming machines, like slot machines and pachinko, are played by one or more players at a time and do not require the involvement of casino employees. Table games, such as blackjack and craps, are played against the house and are conducted by croupiers or dealers. Random number games are based on the selection of numbers by a computer or other random-number generator.

Most casinos make money by offering patrons free spectacular entertainment, transportation, elegant living quarters, and reduced-fare or complimentary food and drinks while gambling. These inducements are designed to increase the amount of money that gamblers spend on gambling activities, thereby increasing their revenues.