A casino, or gaming house, is a place where gambling games are played. These include blackjack, roulette, baccarat, poker, and slot machines. A casino may also offer other activities such as entertainment, shows, and restaurants. In the United States, casinos are most commonly found in Las Vegas and Atlantic City, but are also located in a number of other cities and towns. In addition, a growing number of states allow casino-type games on tribal lands.

Gambling in a casino is legal only if it is permitted by state law. Historically, most states prohibited it. During the second half of the 20th century, however, almost all of the remaining prohibitions were repealed.

In most jurisdictions, the gambling operations of a casino are closely monitored by state and local regulatory authorities. Casinos are required to maintain a certain percentage of their net income as winnings, and must also provide periodic reports on their financial status to these regulators.

A major source of revenue for most casinos is high-stakes gambling. In order to encourage high-stakes gamblers, casinos often offer them free spectacular entertainment, free luxury living quarters, reduced-fare transportation, and many other inducements. In general, casinos attempt to maximize gross profit from all patrons, regardless of the amount they bet.

Because large amounts of currency are handled within a casino, both patrons and employees may be tempted to cheat or steal, either in collusion or independently. For this reason, modern casinos have substantial security measures in place. These typically include a physical security force and a specialized surveillance department.