A casino is a place where a variety of games of chance can be played and where gambling is the primary activity. Modern casinos offer a wide range of entertainment and are often combined with restaurants, hotels, retail shops, and other tourist attractions. Historically, the term casino has also referred to less lavish establishments that housed gambling activities.

In the United States casinos have become a major tourist attraction and are located in many cities and towns. The largest concentration of casinos is in Las Vegas, Nevada, where the industry first started. Other large gaming centers include Atlantic City, New Jersey; Reno, Nevada; and Biloxi, Mississippi. In addition to the main casinos, many Indian tribes operate casinos on their reservations.

Gambling in a casino involves risking real money, and it is not for everyone. A casino has a built-in advantage over the players, and the longer you play, the more money you will lose to the house.

There are many casino games, but the ones that make the most money for the casinos are slot machines and video poker. These games are very simple to understand: the player puts in some money, pulls a handle or pushes a button, and watches the bands of colored shapes roll past on reels (actual physical ones or video representations). If a particular pattern appears, the player wins a predetermined amount of money. Slot machines are the most popular casino game, and they make up a larger percentage of casino profits than any other type of machine.