A casino, also known as a gambling house, is an establishment that allows patrons to wager money or other things of value on games of chance. Many casinos have restaurants, bars, and other entertainment venues. In some countries, casinos are licensed and regulated by government authorities. Other casinos are owned by or located on Native American reservations and are not subject to state laws regarding gambling.

Something about the environment of a casino, probably the presence of large amounts of money, encourages patrons to cheat and steal, either in collusion with each other or on their own. Because of this, casinos spend a lot of time and money on security measures. They use cameras that monitor every table, window and doorway; they employ special chips with built-in microcircuitry that allow casinos to monitor bets minute by minute, so that if there is a statistical deviation from the expected outcome of a game, it can be detected quickly. They even use a high-tech “eye-in-the-sky” system in which cameras are mounted to the ceiling and can be directed by staff to focus on suspicious patrons.

In addition to cameras and monitoring systems, casinos also rely on their familiarity with the patterns of normal behavior in their patrons. Most patrons follow familiar routines in the games they play; it is not hard for casino security personnel to spot anything out of the ordinary. This, combined with the fact that most casino games have a mathematical expectancy of winning, makes it very rare for a casino to lose money on a given day. This virtual assurance of gross profit explains why casinos regularly offer big bettors extravagant inducements, including free spectacular entertainment and transportation and elegant living quarters.