A casino is a gambling establishment that offers various games of chance for customers to wager money. It may also offer entertainment, such as live music and lighted fountains. The profits from these activities provide the billions of dollars that casinos rake in every year. Modern casinos might also include retail shopping and high-end restaurants. However, the vast majority of their profits come from games of chance. Slot machines, blackjack, roulette and craps are among the most popular casino games. In addition, a casino might have a themed design or decoration.

Most casinos have a built-in advantage, called the house edge, which ensures that it will make a profit on all bets placed by patrons. The house edge is not just a mathematical guarantee of profit, but also an insurance policy against the risk that a customer will lose money on a particular game. Because of this virtual assurance of gross profit, most casinos offer free food and drinks, hotel rooms, tickets to shows and even limo service and airline tickets to big bettors.

In the early years of the casino industry, legitimate businessmen were reluctant to invest in a venture with such seamy associations as gambling. As a result, most of the early casinos were funded by organized crime gangsters, who had ample funds from their drug dealing and extortion rackets. As the casino industry grew, the mob became more involved in its operations, taking sole or partial ownership of many casinos and often interfering with decisions about games and security. As a result, some states began to change their anti-gambling laws in the 1970s and 1980s.