A casino is a facility where people play gambling games. In the United States, casinos are licensed and regulated by state governments. Many also offer hotel accommodations, restaurants, entertainment, and shopping. Casinos are primarily operated by private companies, but some are owned or run by local governments. A small number of casinos are located in Native American tribal lands.

The precise origin of gambling is unknown, but it can be traced to almost every society in history. In some cases it has been a part of religious or ceremonial rituals, in other times it was simply a way to pass time. Today, gambling is legal in most states. The games played in casinos are based on chance, but some involve an element of skill. The most common are blackjack, video poker and roulette. Most casinos use mathematically determined odds to give the house a mathematical edge over players. This work is done by expert gaming mathematicians, who are often employed by casinos.

The best casino resorts in the US take the experience to the next level, where casinos are just one part of a massive onsite entertainment complex. In Las Vegas, for example, you can glide down the Grand Canal in a Venetian gondola and gamble on the glitzy floor of the Aria while you enjoy shows by international stars and a full range of upscale amenities, from chef-driven restaurants to a luxury spa.