A casino, sometimes known as a gambling establishment, is a place where people can gamble on various games of chance or skill. Some casinos are large and sprawling, with many different table games, slot machines, and non-gambling entertainment options; others are more modest, focusing on a small number of popular games. Casinos can be found in most countries and, in some cases, are a major source of revenue for the local government.

Security is a top concern for casinos, which spend considerable time and money on it. Video cameras are widely used, and the layout of tables and betting spots is designed to make it easy for security personnel to spot anomalies. In addition, most games have certain routines and patterns that are easily recognizable by trained observers; for example, in card games the dealer shuffles the cards and deals them in a predictable pattern, while slot machine players push buttons in a consistent manner.

The casino business has its critics, however. Some argue that it diverts spending from other forms of entertainment and may even lower property values in the surrounding area. Other criticisms include the prevalence of problem gambling, which accounts for a significant share of casino profits and can cause serious financial problems for the gambler and his or her family.