A casino is a gambling establishment that offers various games of chance and, in some cases, skill. Customers place bets with cash or casino chips and win or lose according to the odds of each game. Some casinos also offer food and drink. A few casinos have theaters for live entertainment. Most casinos are located in places with legalized gambling, such as Las Vegas and Atlantic City in the United States, and Macau in China. Casinos can also be found on some American Indian reservations and in some countries that do not have state-regulated gambling laws.

A large percentage of casino revenue is generated by slot machines and video poker machines. These machines have mechanically determined odds that guarantee the house a profit, which is usually less than one percent. Other popular casino games include roulette, blackjack, and baccarat. In games such as poker where players compete against each other, the casino takes a rake, or a percentage of the money bet, as its commission.

Originally, casinos were designed to be luxurious and glamorous, attracting high-end gamblers like royalty and the aristocracy. They often featured beautiful art and architecture, and some even had their own opera houses. In the twentieth century, however, they became more focused on entertainment and spectacle, with glitzy shows replacing classical music and ballets. These changes coincided with a growing public appetite for recreational gambling, and led to the growth of cities such as Las Vegas and Macau, which have become known for their large casinos.