A casino, also known as a gambling house or a gaming establishment, is a place where people can gamble. Gambling in some form has been a part of human culture since prehistoric times. Modern casinos are usually large and glamorous and offer a variety of games. The most popular are blackjack, roulette, and slot machines. Some are located in large resorts and others are small standalone buildings. In the United States, 40 states now have casinos.

Casinos make billions of dollars each year for the companies, investors, and Native American tribes that own them. In addition, they stimulate regional economies by attracting tourists and business travelers. Some casinos are even built at racetracks, on cruise ships, and on barges and riverboats. Casinos are regulated by government agencies. Security is a major concern for both patrons and employees. Cheating and theft are common. Some casinos have special surveillance systems that monitor the movement of money around the casino floor and the activities of the players, particularly at card tables.

To encourage gambling, casinos give away free goods and services to their best customers. These “comps” include meals, rooms, shows, and limo service. Casinos also track customer behavior and spending patterns, and use this information to target their marketing efforts. In the twenty-first century, many casinos are concentrating their investments on high rollers who can afford to spend much more than average. These people are often given private rooms where the stakes can be in the tens of thousands of dollars.