A casino is a place where people play games of chance for money. Some casinos are massive resorts with multiple restaurants, hotels and shopping centers; others are small card rooms in bars or even truck stops. In the United States, casinos bring in billions of dollars each year for companies, investors, and Native American tribes that operate them. State and local governments also reap casino revenues through taxes and fees.

The best known casino is in Las Vegas, Nevada, but there are many others around the world. Typically, a casino will offer slot machines, blackjack, roulette, craps and other table games. People who spend the most on these games, or on table games like poker and baccarat, earn comps, which can include free food and drinks, hotel rooms, limo service, airline tickets and more. Comps are given based on how much a person plays, and are determined by a number of factors, including time spent playing, the amount of money wagered and the level of stakes played.

Originally, gambling was illegal in all but a few states, so the first casinos were run by organized crime figures with plenty of money from extortion, drug dealing and other criminal activities. When legitimate businessmen realized how much money could be made from gambling, they bought out the mobsters and began opening their own casinos. As the travel industry grows and disposable income increases, casinos continue to grow in popularity around the world.