A casino is a gambling establishment, a place where people can try their luck at gambling. Often, casinos are combined with hotels, resorts, restaurants, retail shops, cruise ships, and other tourist attractions. Casinos also offer live entertainment such as stand-up comedy, concerts, and sports. Some states have legalized gambling, while others ban it or regulate it heavily.

Casinos make their money primarily by taking bets from people who want to win at games of chance. While some games involve skill, most are based purely on luck. The house always has a mathematical advantage over players, which can be expressed as a negative expected value (EVN). Casinos collect the money from gamblers, pay out winning bets, and then reinvest the remainder into new games. They make their profits by collecting a percentage of all wagers, called the vig or rake.

The casino industry is controversial, as it affects the economy of many states, especially those that rely on tourism for a significant portion of their revenue. It also has a reputation for being addictive and harmful to families and communities, as well as a source of compulsive gambling. In addition to the obvious dangers of addiction, casinos harm property values in the surrounding area.

Although gambling probably predates written history, the modern casino as a place to find a variety of ways to gamble under one roof did not develop until the 16th century during a gambling craze in Europe. Casinos are usually heavily guarded, with security personnel stationed around the tables and slot machines watching for blatant cheating or stealing. They may have catwalks in the ceiling that allow security staff to look down through one-way glass on patrons at table games or slots, and they use high-tech eye-in-the-sky surveillance systems that can zoom in on specific suspicious individuals.