A casino is a place where gambling activities take place. In addition to offering a variety of games where people can gamble, casinos usually offer restaurants, free drinks, stage shows and other entertainment. They may also offer hotel rooms and non-gambling game rooms, bars, swimming pools, spas and other amenities to attract customers.

Casinos make money by charging a fee for each bet placed by a patron. This fee is called a vig or rake. It is usually equal to a small percentage of the amount that a player wins or loses. Casinos must calculate their house edge and variance for each of their games, so they employ mathematicians who specialize in this field. They must know not only the mathematical expectation of winning, but also the amount that they need in cash reserves (known as their bankroll).

Slot machines are among the most popular casino games. A player inserts a coin or paper ticket, pulls a handle or pushes a button, and watches variable bands of colored shapes roll on reels (physical or virtual). When a pattern appears, the machine pays out a predetermined sum of money. The game is purely random and doesn’t require any skill.

Most casinos also offer card games like blackjack and baccarat, and many feature dice games like keno and trente et quarante. Card and dice games can involve a high degree of skill, so casinos have to enforce rules designed to prevent cheating, such as requiring players to keep their cards visible at all times. In addition to using cameras and other technological measures, casino security staff watch the floor closely for any improprieties.