A casino, or gaming establishment, is a place for certain types of gambling. Modern casinos are like indoor amusement parks for adults, with the bulk of their entertainment coming from gambling games such as slot machines, blackjack, roulette, craps, and keno. Casinos often feature restaurants and live entertainment. Some have pools, spas, and even hotels. Casinos make their money primarily from the games, although they do earn some income from food, drinks, and other amenities.

Gambling in some form has been a part of human culture for millennia. Evidence of dice from 2300 BC China and card games from 500 AD Rome indicate that humans have always been keen on chance. The modern casino, however, did not appear until 1931 in Nevada. Before then, most casino gambling was illegal.

Casinos use a variety of tricks to persuade people to gamble. They are designed around noise, light, and excitement, with the blaring of music and clang of coins falling from slot machines to attract attention. They also entice people with the promise of comps (free or discounted meals, drinks, shows, and room charges). Many casinos offer loyalty programs that track patron behavior to develop a customer database.

In order to prevent cheating or theft, casinos employ a wide range of security measures. Most have video surveillance systems and some have catwalks in the ceiling that allow surveillance personnel to look down through one-way glass at a table or slot machine. The bright lights used in many casinos are a deterrent to thieves, as they tend to cause drowsiness.