A Casino is a building that accommodates gambling. Customers may gamble by playing slot machines or other games of chance and some skill (e.g., craps, roulette—for more see casino games).Slot machines are commonplace in Casino.

Game rules usually have mathematically determined odds built in that ensure the house retains an advantage over the players. This advantage is called the edge. Payout is the percentage given to players. Some statistically even games may take a commission or tax (a "rake") on bets customers make against each other (e.g. poker). Casino are often placed near or combined with hotels, restaurants and other vacation attractions to encourage long stays.

The term originally meant a small villa, summerhouse or pavilion built for pleasure, usually on the grounds of a larger Italian villa or palazzo. There are examples of such casinos at Villa Giulia and Villa Farnese. During the 19th century, the term Casino came to include other more public buildings where pleasurable activities, including gambling and sports, took place. An example of this type of building is the Newport Casino. Eventually this term in Italian now designates a bordello (also called "casa chiusa" literally "closed house"), while the gambling house is spelled Casino with an accent.