A casino is a gambling establishment where patrons can wager money and receive prizes. In the past, most casinos were private clubs for members only, but in the twentieth century nearly every country changed its laws to permit public gambling. In modern times the majority of casino revenue comes from slot machines. Players put in a coin or paper ticket, pull a handle or push a button and watch as the varying bands of colored shapes roll on reels (real physical ones or a video representation). A winning combination gives the player a predetermined amount of money.
A small percentage of casino revenue is also derived from poker, dice and other table games. Some casinos have a wide range of amenities and a focus on customer service; a deluxe hotel and spa, for example. In the United States casino perks for big bettors include free rooms, meals, shows and transportation (even limo services and airline tickets).
Because of the large sums of money handled within a casino, both staff and patrons may be tempted to cheat. Casinos have a variety of security measures to prevent this, including surveillance cameras. Security employees monitor these cameras and watch the game to spot suspicious patterns. In addition, pit bosses and tables managers have a broader view of the casino, looking for blatant tricks such as palming cards or marking dice.