A casino, also known as a gambling house or a gaming establishment, is an establishment where various forms of gambling are conducted. It offers slot machines and table games (like poker, blackjack, and roulette) in addition to entertainment shows. To gamble at a casino, the customer must be of legal age and follow the rules and regulations of the establishment.

Casinos are generally supervised by a team of security personnel to ensure the safety and integrity of the casino property and patrons. They also use technology to monitor the actual play of games. For example, betting chips with built-in microcircuitry interact with electronic systems to allow casinos to oversee bets minute by minute, and roulette wheels are electronically monitored regularly to discover any statistical deviations from expected results.

In most countries, it is illegal to run a casino without a license. However, casino-style gambling has existed in some form or another throughout much of human history. It has been practiced in ancient Mesopotamia, the Roman Empire, the Middle East, and many other societies. Its popularity has risen and fallen over time, and in the modern world casino gambling is available in many states in the United States and around the globe.

Like any industry in a capitalist society, casinos are in business to make money. Successful ones rake in billions each year for the companies, investors, and Native American tribes that own and operate them. They also reap profits from players in the form of fees and taxes. In order to maximize profit, most casinos offer a variety of perks, or comps, to encourage gamblers to spend more money than they would otherwise and to reward loyal customers.