A casino is a facility where people can gamble. The casino industry is regulated by governments worldwide. The United States has the largest number of casinos, followed by Europe. Most casinos are located in cities such as Atlantic City, Las Vegas and Chicago. Casinos can also be found on American Indian reservations and are not subject to state antigambling statutes.

Most casino games are based on chance. The house edge and variance of each game are calculated by mathematical formulas that can be analyzed by a team of specialists known as gaming mathematicians and analysts. This allows the casino to monitor its gross profit, and also ensures that no single patron can win more than the house can afford to pay.

Many casinos employ a dedicated security force to patrol the premises and respond to calls for assistance or reports of suspicious or criminal activity. In addition, modern casinos use cameras and other technology to supervise the play of their games; for example, betting chips have built-in microcircuitry that enables the casino to track the exact amounts wagered minute by minute, and roulette wheels are regularly electronically monitored to discover any statistical deviation from expected results.

The casino is a popular gathering place for gamblers and others seeking entertainment. It has contributed to the development of gambling in the United States, and is a major source of tourism revenue. It is also a significant source of income for many localities.