A casino is an establishment for gambling. Some casinos are built in or combined with hotels, restaurants and retail shops; others are stand-alone buildings. In the United States, casinos are usually located in or near cities and are regulated by state law. Various casino games are played, including poker, blackjack, roulette, and slot machines. Many casinos also offer sports betting and have bars and night clubs.

Casinos make money by charging a small percentage of every bet placed on their machines and tables. This is called the house edge, and it allows the casino to make a profit even when some of the bets lose. This house edge can be lower than two percent, but it adds up over the millions of bets made in a casino.

Successful casinos bring in billions of dollars each year for the companies, investors, and Native American tribes that operate them. State and local governments also reap significant revenue from casino gambling. Critics, however, say that the industry takes away spending from other forms of entertainment and that the social costs associated with problem gambling outweigh any economic benefits.

In 2005, the average casino gambler was a forty-six-year-old female from a household with an above-average income. These patrons, who often have more vacation time and spending money than younger adults, make up the largest group of casino visitors. But compulsive gamblers generate a disproportionate share of casino profits, and studies show that the cost of treating problem gambling can offset any revenue gains from the operation of a casino.