A casino is a gambling establishment where people can place wagers on various games of chance. The games may involve skill, such as poker, or pure luck, like roulette and blackjack. Many casinos also offer food and drink, and some even have hotels. In the United States, there are over 1,000 casinos, with Las Vegas having the largest number. Other cities with large numbers of casinos include Atlantic City, New Jersey and Chicago, Illinois.

A modern casino usually has a physical security force and a specialized surveillance department. The security forces patrol the floor and respond to calls for assistance or reports of suspicious or definite criminal activity. They also operate the casino’s closed circuit television system, known as the eye in the sky. The surveillance departments watch both the patrons and the machines to prevent cheating or stealing.

Because of the large amount of money that changes hands within a casino, both patrons and staff can be tempted to try to cheat or steal from each other. In collusion or independently, they can use a variety of tools to achieve this, including special tricks with cards and dice, and hidden cameras. To combat these temptations, casinos generally have strict rules about behavior and dress.

Many casinos also use scents to manipulate people’s behavior. Studies have found that when people are exposed to a pleasant smell, they gamble longer and spend more. For example, one casino scented its ventilation system with the aroma of fresh baked bread. Another conditioned its patrons by playing soothing music on the casino floor, believing that it would encourage them to place bets without thinking.