A casino is a building or room where gambling games are played. Casinos are most commonly found in resorts, hotels, and restaurants, as well as some cruise ships. They offer games of chance, including poker, blackjack, roulette, baccarat, and slot machines. Some casinos also offer sports betting and horse racing. Some casinos are known for their extravagant decor and size, while others are famous for their entertainment offerings.
Gambling games probably predate recorded history, with primitive proto-dice and carved knuckle bones being found in archaeological sites. However, the modern casino as a venue for gaming did not develop until the 16th century when a gambling craze swept Europe. This casino phenomenon was facilitated by the fact that most games had mathematically determined odds that guaranteed the house an edge over the players, which is known as the house advantage. The house edge varies from game to game, but it is always there. Casinos make money by calculating a commission on all winning bets, which is called the vig or rake. They also give out free items to gamblers, called comps.
While security in a casino starts with a full staff of floor personnel, technology has greatly expanded the surveillance capabilities of casinos. For example, in table games, chips are now wired to a central system that enables casinos to oversee the exact amount of money wagered minute-by-minute and warn them of any statistical deviation from expectations; electronic systems monitor roulette wheels for anomalies.