A casino is a gambling establishment where patrons wager on games of chance, or skill, to win money. The casino industry is largely based in the United States, where over 30 states have legalized casino gambling. In addition to the excitement of gambling, casinos are known for elaborate themes and entertainment such as musical shows, lighted fountains, shopping centers and themed hotels. The majority of the profits a casino makes, however, are from the gambling games themselves. Slot machines, roulette, blackjack, poker and craps provide the billions of dollars in profits that the industry rakes in each year.

Gambling is considered addictive, and some people have trouble controlling their spending. This is why casinos spend a great deal of time and money on security, especially on the casino floor. Casino employees keep their eyes on the games and casino patrons, watching for blatant cheating and looking for betting patterns that may indicate that someone is stealing. Many casinos also decorate in bright colors, like red, which is believed to help gamblers lose track of time and concentrate better on the game.

Casinos are expensive to operate, and attracting large numbers of visitors is essential. For this reason they employ many marketing tricks, including the use of dazzling light displays and the sound of bells and whistles to lure customers. In the United States, more than 15,000 miles of neon tubing are used to illuminate the casinos along the Las Vegas Strip.