A casino is a building or room where people play games of chance. In the United States, casinos are usually located in major cities such as Las Vegas or Atlantic City and on Native American reservations. Many also have restaurants, retail shops, and other entertainment options. A casino may also be a large standalone building or a part of a hotel/resort.

Something about the atmosphere of casinos, perhaps because they deal in large sums of money, seems to encourage cheating and stealing. This is why casinos spend so much time, energy and money on security. In addition to obvious visible security measures, there are subtle ones too: the ways dealers shuffle and deal cards, the location of betting spots on tables, and even the expected reactions and motions of players follow certain patterns. These can make it easier for security to spot things that are out of the ordinary.

In addition to their glitz and glamour, casinos provide billions of dollars in profits each year for the corporations, investors, and Native American tribes that own them. They also generate revenue for the governments that license and regulate them. However, some studies suggest that the social costs of compulsive gambling (including lost productivity) more than offset any economic benefits from casinos. This is why some state and local governments oppose casino expansion. Despite this, a number of communities have built or expanded casinos. Some, such as the one in Niagara Falls, even offer both U.S. and Canadian versions of the same casino, so you can enjoy the flashy lights on the U.S. side, and the quainter, less-crowded Canadian side.