A casino or gambling house is an establishment that offers various types of gambling. Modern casinos are often combined with hotels, resorts, restaurants, retail shops, and other tourist attractions. Some casinos host live entertainment events such as stand-up comedy, concerts, and sports matches. Most casinos offer a variety of gambling games, including craps, roulette, blackjack, poker, and video poker. Some casinos also have keno and bingo halls.

Historically, casinos were designed to be visually appealing and comfortable for patrons. Many casinos have elaborate interior architecture, and some are decorated in opulent styles. In modern times, most casinos rely on technology for security and customer service. Some of these features include slot machines with built-in microcircuitry that monitors the number of coins deposited and the amount of money won; table games with electronic systems that oversee the amount of money wagered minute by minute to quickly discover statistical deviations from expected results; and wholly automated versions of traditional casino games such as baccarat, which have a similar appearance to real tables but function in a different manner.

Because large amounts of cash are handled within casinos, they are prone to theft by both patrons and employees. To prevent this, most casinos have a physical security force as well as a specialized surveillance department that monitors the operation. The security forces and the surveillance department work closely together to deter crime. Casinos are also known for offering perks to attract gamblers and encourage them to spend more money. These perks, which are known as comps, may include free hotel rooms, food, drinks, and show tickets.