A casino is an establishment for certain types of gambling. These facilities are sometimes combined with hotels, resorts, restaurants, retail shops, and other entertainment venues. They may also feature sports betting, or be located on ships or in other places where gambling is legal. In the United States, casinos are licensed and regulated by state governments. Successful casinos bring in billions of dollars each year for the companies, investors, and Native American tribes that operate them. In addition, they generate taxes and other payments for local communities.

The casino industry is highly competitive, with the top five operators earning more than $20 billion in revenue in 2014. Most casino games involve some element of chance, but a few have a significant skill component. For example, blackjack and video poker offer players a set of optimal strategies that maximize their expected value. The mathematical analysis of these games is called game theory, and its practitioners are known as gaming mathematicians and analysts.

In the United States, most casinos are built in cities or towns and serve primarily local patrons. In 2005, the majority of casino gamblers were adults over forty-five who came from households with above-average incomes. This demographic is characterized by having more free time and available spending money than younger generations.

The word casino is derived from the Italian cazino, meaning “little house.” The world’s oldest casino is in Venice, and it was once a haunt of royalty and aristocracy. It is now a lavish palace where visitors can try their luck at roulette and blackjack.