A casino, also known as a gaming house or a gambling establishment, is a place where people can gamble. Many casinos combine this activity with hotel and retail shopping, restaurants, cruise ships and other forms of entertainment. The precise origins of gambling are unclear, with primitive games such as knucklebones and dice likely dating back thousands of years. Modern casinos are often large complexes that offer a wide range of entertainment options under one roof, such as musical shows and lighted fountains. However, it is the games of chance that bring in the billions of dollars in profits that keep casinos in business.

A major source of revenue is slots, which are a popular form of amusement with both players and non-players alike. In this type of machine, the player inserts cash or paper tickets with barcodes, and a computer program determines whether the ticket is a winner. Unlike other casino games, slot machines do not require any skill or strategy. Varying bands of colored shapes roll on reels (actual physical or video) and if the right pattern appears, the player wins a predetermined amount of money.

In the 1950s, mafia leaders pumped huge sums of cash into Reno and Las Vegas, establishing their own casinos. But mob money brought with it a reputation for criminality, and legitimate businesses were reluctant to take on the risk. Real estate investors and hotel chains soon realized that they could make more money by running their own casinos without the mob’s interference, and this was a turning point in the evolution of the modern casino industry. Today, the most successful casinos are run by businesspeople with deep pockets.