A casino or gaming hall is a type of gambling establishment where patrons can gamble by playing games of chance, in some cases with an element of skill. Most casinos offer table games such as blackjack and craps and video poker, which are conducted by live dealers, croupiers, or mechanical devices. Some casinos also offer other types of gaming, such as keno and roulette. In the United States legal casinos are concentrated in Las Vegas and a few other cities, but are spreading throughout the country as more jurisdictions amend their laws to permit them.

In addition to the traditional gaming tables, most modern casinos employ technological measures to prevent cheating and theft. Security cameras, for example, are placed throughout the facility and monitor activity to identify suspicious patrons. Similarly, betting chips have microcircuitry that interacts with electronic systems to oversee the exact amounts wagered minute by minute and warn staff if any unusual deviation occurs.

Gambling in its various forms has been a popular form of entertainment throughout history. The precise origins are unknown, but it is generally believed that gambling in some form has been a part of nearly every culture worldwide. It has become especially prevalent in the modern world, where it is considered an important component of the leisure industry and is a major source of revenue for many governments.