A casino is a building that offers chances to win money in games of chance. A wide range of casino games are offered in modern casinos, from poker and blackjack to roulette and craps. Many states have legalized casino gambling, and there are more than 500 casinos in operation worldwide. Casinos attract 51 million people—an estimated quarter of the adults over 21 in the United States—a year, and they generate billions of dollars for owners. The casinos that offer the most dazzling spectacles—and the highest profits—are on the Las Vegas Strip, but there are also casino buildings in places like Atlantic City and Iowa, as well as the massive hotel-casino complexes in Macau and the Philippines.

While elaborate theme parks and dazzling musical shows might draw people to casino floors, these gambling venues wouldn’t exist without the games of chance that provide the profits. Slot machines, blackjack, poker and other card games, along with keno and baccarat, make up the majority of the billions that casinos rake in each year.

Casinos have a lot of controls to keep their patrons safe, from the design of the casino floor to the strict rules on how players must conduct themselves. Something about gambling (maybe it’s the large amounts of money) seems to encourage cheating, stealing and other forms of dishonesty, which is why casinos have so many security measures in place. For example, the casino chips are purchased from reputable suppliers who maintain tight control over their inventories. Then they’re carefully inspected at the casino before being used on the floor and then stored in the casino vault. When the chips are worn out, a specialist chip destruction firm grinds them up while being watched by security personnel.