A casino is a building where people can play games of chance. While a modern casino may feature restaurants, free drinks, elaborate stage shows and other luxuries, it would not exist without games of chance—slot machines, blackjack, poker, baccarat, roulette, craps and more—that provide the billions in profits raked in by casinos every year.

In the past, casinos often used bright and sometimes gaudy floor and wall coverings to create a stimulating and cheering atmosphere. The color red was particularly popular, because it has been shown to make gamblers lose track of time. In the 1990s, casinos began deploying video cameras and electronic monitoring systems to supervise their games. For example, a machine called an eye in the sky is a high-tech version of a pit boss, watching over table games with a wide view and detecting any deviations from expected results. Other technologies include chip tracking, which monitors each betting pattern; and roulette wheels with built-in microcircuitry that detects abnormalities in their rotational speed.

The owners of a casino must be careful to balance the need to attract a large and diverse audience with the fact that a large percentage of their gross profit comes from those who spend the most. As a result, casino managers are careful to reward high-spenders with comps such as free hotel rooms and meals, tickets to shows, limo service and airline tickets. Casinos also encourage loyalty by offering a variety of bonuses to players who use certain payment methods. These rewards vary from no-deposit bonus chips to free spin allowances.