When most people hear the word casino, they imagine the bright lights and big money of Las Vegas or Atlantic City. But casinos can be found across the United States, from tiny mountain towns with 19th century Wild West buildings housing slot machines and poker tables to large cities offering world-class resorts and luxurious gambling opportunities.

The precise origins of casino are obscure, but gamblers have always sought ways to beat the house and have long been a feature of human society. In fact, the very first games of chance were probably based on card playing, although it is uncertain whether gambling was ever legalized in Ancient Mesopotamia, Rome or Greece.

Casinos make their profits by taking a percentage of bets placed on the tables or slots. They also offer complimentary items (known as comps) to players, especially high rollers who spend a lot of money. Comps include free rooms, meals and tickets to shows, but can even extend to limo service and airline tickets.

While most of us think of casinos as places where luck and skill dominate, there is a significant element of risk involved in any type of casino game. And the large amounts of money handled within a casino can be tempting to patrons and staff, who may be tempted to cheat or steal, either in collusion or independently. This is why casinos spend a great deal of time and money on security measures. Among them are sophisticated cameras that keep an eye on every table, window and doorway, and can be focused to watch specific suspects by security workers in a room filled with banks of monitors.