A casino (also called a gambling hall, gaming room or club) is a facility where people can gamble by playing games of chance or skill. Some casinos specialize in a particular game, while others offer a wide range of games. In most jurisdictions, casinos are regulated by law to ensure honesty and integrity. Some casinos, such as those in Las Vegas and Macau, are world-famous for their luxury, entertainment options and high-stakes gambling. The Bellagio, for example, is famous for its dancing fountains and luxurious accommodations and is a popular destination for both casual and high-stakes gamblers.

In the United States, casinos are largely legal in Nevada, where they attract visitors from throughout the country and the world. Other states where casinos are located include Atlantic City, New Jersey; Detroit; Chicago; and the state of Iowa, which has two casinos. Native American casinos are also increasing in number.

Casinos are designed to encourage gambling by providing an atmosphere that is noisy, bright and exciting. They may use colors such as red, which is believed to make people lose track of time; there are usually no clocks on the walls. People are surrounded by other gamblers and waiters who serve drinks. Often, the drinks are free of charge.

Because of the large amounts of money involved, security is a major concern in casino operations. Patrons and staff may be tempted to cheat or steal, either in collusion or independently; for this reason, most casinos have extensive security measures. These may include cameras and sophisticated software that monitors the actions of players and spots statistical deviations from expected results.