When most people think of a casino, they picture the sprawling resorts along the Las Vegas Strip. They are big and slick, filled with gambling options and elaborate attractions. While musical shows, lighted fountains and shopping centers draw in customers, casinos are mostly based on games of chance that earn billions in profits for their owners every year. Slot machines, blackjack, roulette, craps and baccarat are some of the most popular games that help to keep the industry alive.

Gambling is a highly addictive activity, and casinos use a variety of methods to lure in gamblers. Bright lights are one big draw; more than 15,000 miles (24,100 km) of neon tubing illuminates the Las Vegas casinos. Sounds also contribute to the atmosphere; a casino floor is full of bells, whistles and clangs that play on human auditory nerves. Moreover, humans are attracted to shiny objects; hence the numerous flashing lights and mirrors that cover a casino.

Many casinos were originally founded by organized crime figures who had plenty of cash from their drug dealing, extortion and other illegal rackets. As such, they were able to finance their operations without having to worry about the seamy image of gambling. Mafia money helped to make Nevada the casino capital of the United States.

Casinos make money by taking a percentage of the bets that their patrons place, or the house edge. It can be as low as two percent for some games, but this small advantage adds up over the millions of bets that are made. In addition, the casino often takes a share of the pot in games where players play against each other, such as poker and baccarat.