A casino is a gambling hall, where patrons can gamble, play games of chance, and win or lose money. The modern concept of a casino is based on nineteenth-century European gambling houses, where patrons would gather for social occasions and play games such as roulette and blackjack. Today, casinos have become a popular tourist attraction, with many offering a wide variety of casino games.

In order to maximize revenue, casinos rely heavily on high rollers who spend much more than the average gambler. These patrons are often given special rooms for their betting, where the stakes may be in the tens of thousands of dollars. In addition, they are pampered with comps such as free hotel rooms, buffets, and show tickets. High rollers make up only five percent of casino customers, but they generate 25 percent of the profits.

Despite their popularity, casinos face several challenges. Because of the large amounts of cash handled within a casino, both patrons and staff can be tempted to cheat or steal. To prevent this, casinos invest considerable time and money in security measures. Video cameras monitor the gambling areas, while computer technology can supervise specific games. For example, chip tracking allows a casino to oversee the exact amount of money wagered minute by minute; and specialized software can quickly discover any statistical anomaly on a roulette wheel or card game.

Casinos are also a source of controversy because they can be a drain on local economies. Critics say that casino revenue lures away spending from other forms of local entertainment, and that the cost of treating problem gamblers and lost productivity offset any economic benefits.