A casino (from the Spanish word kasino, meaning “gambling house”) is an establishment for gambling. It may be located on land or in the sea, and it can also refer to an entertainment complex or a group of such facilities. Some casinos specialize in specific types of gambling, such as blackjack or video poker. Others feature multiple games, including slot machines and roulette. Most of these casinos are located in areas that are legally permitted to offer gaming, although a few states still have antigambling laws.
A modern casino is usually supervised by a team of security experts, who are assisted by specialized surveillance departments. These security forces monitor the movements of casino patrons, both inside and outside the building, as well as the casino’s closed circuit television system, known as the “eye in the sky”. Casinos also employ a variety of other methods to protect their assets. These include chip tracking, in which chips with microcircuitry are used to record the amounts wagered minute by minute; and specialized roulette wheels that are monitored electronically for any statistical deviation from their expected behavior.
Most games of chance have a mathematically determined advantage for the house, which is called the house edge. In games where skill can affect the outcome, such as blackjack, this advantage is lessened through a knowledge of basic strategy. In games where players compete against each other, such as poker, the casino makes money through a commission, or rake, charged to each player.