A casino is a place where people gamble. These establishments may also have restaurants, bars, and other entertainment. Some are part of resorts or hotels, and others stand alone. Most casinos offer a variety of gambling games, including poker, blackjack, roulette, and slot machines. Some have live entertainment such as shows or comedians.

In the past, many casinos were run by organized crime gangsters. Mobsters were wealthy from drug dealing, extortion, and other illegal activities, and they liked the money they could make from casino gambling. They were willing to take on the risky business of running a casino, even though gambling was still illegal in most states. In addition to providing the capital, they often took on management roles and influenced the outcome of some games.

Something about the gambling environment encourages patrons to cheat and steal, either in collusion with each other or on their own. This is why casinos spend a lot of time and effort on security. They must be vigilant against bribery, theft, and other forms of corruption, which can easily occur given the large amounts of money handled in a casino.

Casinos have a built-in mathematical advantage of a few percent, which they use to generate profits over long periods of time and millions of bets. In order to make up for this edge, they compensate (or comp) the most frequent and valuable customers with free tickets to shows or other events, food and drinks, hotel rooms, reduced-fare transportation, and other amenities. They also offer a wide range of table and slot machine games with different payback percentages to appeal to a variety of players.