A casino, also known as a gambling house or a gaming establishment, is a place where people can gamble. Casinos are often combined with hotels, restaurants, retail shopping, and other tourist attractions. Some casinos are operated by governments. Others are owned by private corporations. Still others are owned by religious or charitable organizations. Most countries have legalized casinos.

Casinos earn money by giving patrons a statistical advantage over other players. That edge is usually small, less than two percent, but it adds up over millions of bets. This virtual assurance of profit allows casinos to spend lavishly on entertainment and infrastructure. For example, some casinos have fountains, giant pyramids or towers, and replicas of famous landmarks. They may also offer free shows, hotel rooms and limo service to big bettors.

Gambling addiction has become a serious problem in many parts of the world. Compulsive gambling is estimated to affect five percent of casino patrons. The cost of treating the addicts and lost productivity at work can offset any economic gains a casino might generate. Casinos are also sometimes criticized for being a source of social problems such as crime, substance abuse, and family distress.

The largest casinos in the world are located in Las Vegas, Atlantic City, and the Chicago area of the United States. However, more and more states are allowing casinos to open. Many are being built near cities and airports. This trend is expected to continue as the population of baby boomers approaches retirement age.