A casino, or gaming hall, is a place where people play gambling games. Some casinos are famous for their luxurious facilities, while others focus on live entertainment and dining. Most casinos offer a variety of games, from blackjack and roulette to slot machines and video poker. Some casinos also have sportsbooks and racetracks. Some casinos are open around the clock, while others stay open for a few hours or less.

Casinos make money by taking a small percentage of each bet, often less than two percent. This may not seem like a lot, but over the millions of bets placed each year it adds up. In addition, the profits from the games provide funds for casinos to build impressive hotels, restaurants, and fountains, as well as to display statues and replicas of landmarks.

During the 1980s casinos began opening on American Indian reservations, which are exempt from state antigambling laws. Real estate investors and hotel chains soon realized the potential of casinos, and they bought out the gangsters, who had controlled many of them. The new owners instituted policies that made it difficult for mobster associates to use the casinos, and they improved security measures.

In the 1990s casinos greatly increased their use of technology to supervise games. For example, betting chips have built-in microcircuitry that allows them to communicate with surveillance systems; roulette wheels are electronically monitored minute-by-minute for any deviation from their expected patterns. Casinos also rely on video cameras for general security.