A casino, or gaming hall, is a place where people gamble on games of chance. Casino games include slot machines, roulette, craps, baccarat, blackjack, and poker. Some casinos also have shows and restaurants. Most casinos have a high minimum age for patrons.

The precise origin of gambling is not known, but it is clear that betting in some form predates recorded history. The modern casino, however, developed only in the late 19th century. It is generally considered to have been influenced by the Monte Carlo casino, which opened in 1863. Today, more than 100 million people visit casinos worldwide every year. The casino industry is dominated by a few large companies, most of which are in the United States.

In 2005, a study by Roper Reports GfK NOP and the U.S. Gaming Panel found that the average casino patron was a forty-six-year-old female from a household with above-average income. The study also found that a majority of casino gamblers were married.

Casinos use a variety of tricks to draw in gamblers, including the dazzling lights and sounds that beckon passersby from street level to gaming rooms. Many casinos are arranged in maze-like fashions to entice visitors. Many casinos offer free or reduced-fare entertainment and transportation to lure gamblers.

Although casino gambling does bring in money, some argue that the negative social and economic impact of compulsive gambling offset any benefits. Critics of the industry contend that the revenue generated by casino gambling shifts dollars from other forms of local entertainment and that the expense of treating problem gamblers offsets any profits.