A casino is a gambling establishment where a variety of games of chance can be played. In modern times, a casino is often an elaborate resort that features restaurants, nightclubs and other entertainment, but it can also be a small card room in a rural area or on a Native American reservation. Successful casinos generate billions of dollars each year for their owners, investors and local governments.

A few states are known for their huge casino resorts, including Las Vegas, Nevada and Atlantic City, New Jersey. Many other states have legalized gambling, and some casinos operate on riverboats or in racetracks as racinos. Casino-type game machines are also found in truck stops and bars, as well as at some grocery stores.

While free stage shows and lighted fountains add to the entertainment value of a casino, the vast majority of its profits come from gambling. Most casinos feature a wide range of popular games, but some have specialized in particular games or in attracting certain patrons. For example, roulette is a common game in Europe, where casinos lower the house advantage to less than one percent to attract large bettors. In America, slot machines and (since the 1980s) video poker machines are the economic mainstay of most casinos, because they draw high volumes of low-wagering players at a relatively inexpensive cost per spin.

Because of the large amounts of money handled within casinos, staff and patrons may be tempted to cheat or steal, either in collusion or independently. This is why most casinos have security measures, such as surveillance cameras.