A casino is a large room or building equipped for gambling. It may also refer to:

Like any industry in a capitalist society, casinos exist to make money. They rake in billions of dollars each year for the companies, investors, and Native American tribes that own and operate them. The profits are used for a variety of purposes, including maintaining the casino and paying its staff.

To maximize their gross profit, casinos employ a variety of marketing strategies. They lure people into their establishments with free drinks, subsidized hotel rooms, and other amenities. They also rely on technology to monitor and track the activities of patrons and employees. For example, chips with built-in microcircuitry allow casinos to oversee the exact amount of money wagered minute by minute; roulette wheels are electronically monitored regularly for statistical deviations from expected results.

The bright and often gaudy interiors of casinos are designed to stimulate the senses. They are usually decorated in red, a color that is associated with luck and wealth. They also do not display clocks, which are believed to distract people from losing their focus.

Some casinos are known for their prestigious restaurants and live entertainment, such as shows and sports events. They can be found in countries around the world and are often located near airports or tourist attractions. In some cases, they are operated by local governments, private businesses, or religious organizations. In the United States, state laws regulate how casinos are licensed and regulated.