A casino, also known as a gambling house or a gaming establishment, is a building or room where people can play certain types of gambling games. Casinos are most often built near or combined with hotels, restaurants, retail shops, cruise ships and other tourist attractions. Some casinos are open 24 hours a day and feature a variety of gambling activities, from slot machines to table games like blackjack and poker.

Something about gambling (maybe the potential for large jackpots) encourages people to cheat, steal and otherwise try to manipulate the results of a game rather than relying on pure chance. This is why casinos spend a lot of time and money on security. Elaborate surveillance systems provide a high-tech eye-in-the-sky, with cameras that watch every table, light switch and doorway in the entire facility, or can be focused on specific patrons by workers in a room filled with banks of monitors. Casinos also hire mathematicians who specialize in games analysis, to determine the house edge and variance for each game they offer.

While musical shows, lighted fountains and lavish hotels draw in the crowds, the bulk of casino profits come from games of chance. The popular casino games of craps, baccarat, roulette, blackjack and poker contribute the billions in annual profits to U.S. casinos. However, studies indicate that casinos bring more trouble than good to a local economy: lost productivity from addicted gamblers offsets any economic benefits. And some towns have even banned them.