A casino is a gambling establishment where patrons wager money on games of chance or skill. In addition to roulette and craps, most casinos offer card games such as blackjack and poker; video poker machines; and keno. In many countries casinos are licensed and regulated.

Gambling almost certainly predates recorded history, with primitive protodice and carved six-sided dice found in ancient archaeological sites [Source: Schwartz]. But the modern casino did not develop until the 16th century, when a gambling craze swept Europe, prompting Italian aristocrats to hold private parties at clubs called ridotti, where they could enjoy a variety of games without fear of legal sanction.

Casinos rely on the mathematical expectation that each game will produce an overall profit, known as the house edge. This means that the average player, over time, will lose more than they win. However, casinos are not aiming to bankrupt their customers in one sitting; they want to make enough money to attract players and keep them coming back for more. For this reason, they give certain patrons free items and services (known as comps) based on the amount of money they spend on gambling.

Casinos also make their money by taking a percentage of the total bet, or rake, on some table games. In addition, they offer a number of other revenue sources, such as food and drink sales, hotel rooms, and shows. Despite the revenue, some studies indicate that casinos do not bring net economic benefits to a community and may even cause a shift in spending from other sources of entertainment and may lead to gambling addictions, which cost communities dearly in terms of lost productivity and welfare expenditures on problem gamblers.