A casino is a gambling establishment that offers a variety of games of chance and skill. The games can be played at tables or on machines, and are supervised by dealers. The casino also offers food, drinks and entertainment. Successful casinos bring in billions of dollars each year for owners, investors and state and local governments. Casino gambling has spread worldwide. There are now more than 3,000 legal gambling establishments in the United States. Some of the largest are located in Las Vegas, Atlantic City and New Jersey. In addition, many American Indian reservations have casinos.

The main income for most casinos is derived from the sale of slot machine and video poker games. These machines require only a small percentage of each bet to pay out winnings, but generate high volumes of play and are easy to adjust for any desired profit margin. American casinos are also renowned for their spectacular shows and fine dining. Such distractions serve as a welcome break from the monotony of the gambling floor and help patrons to celebrate their wins or commiserate their losses.

Because casinos deal with large amounts of money, they employ extensive security measures. Casinos have cameras in every room that are linked to monitors throughout the facility. Casino employees watch these monitors and are able to spot suspicious patrons, either in collusion with one another or individually. Casinos also prohibit anyone with a history of mental illness from entering the premises. In addition, they will not allow gamblers who have signed up on a state or casino self-exclusion list.