A casino is a gambling establishment where people can play games of chance for money or other prizes. Casinos can also be called gaming houses or simply gambling halls. People can play a variety of casino games, including card games, dice games, and roulette. Some casinos offer free drinks to patrons, and some even have restaurants. In the United States, casinos are regulated by state law. Some states have banned them completely, while others permit them only on Indian reservations.

A specialized security force patrols casinos and responds to calls for help or reports of suspicious or definite criminal activity. Some casinos use catwalks in the ceiling that allow surveillance personnel to look down, through one-way glass, on activities at tables and slots. Some casinos also have a special computerized system that monitors activity in real time, and can record or replay images.

While musical shows, lighted fountains, shopping centers, lavish hotels and themed restaurants all help attract and retain customers, casinos would not exist without the billions of dollars in profits from gambling. The most common game is slot machines, but blackjack, craps, roulette, baccarat and other table games provide substantial revenue as well.

The popularity of casino gaming has grown significantly worldwide in the 20th century. Many states changed their laws in the 1980s and ’90s to permit gambling, and casinos began opening on American Indian reservations. The first casino outside of Nevada opened in Atlantic City, New Jersey, in 1978, and in the 1990s casinos were introduced on riverboats in Iowa and elsewhere.