A casino is a facility for certain types of gambling. In addition to gaming tables and slot machines, casinos often contain entertainment venues and retail shopping. Some casinos also feature restaurants and hotels. Most of these casinos have security measures in place to prevent cheating and stealing, either by patrons or employees. Some of these measures include a large number of cameras in the casino, catwalks that allow surveillance personnel to look down at table and machine activities from overhead, and other technology to ensure fair play.

Gambling is a popular pastime in most societies, and casinos have become major attractions. The modern casino is often a complex building that includes various rooms for different types of games, such as poker, blackjack, and roulette. Most of these games involve a degree of skill, but the outcome of many is determined by chance. The house has a mathematical advantage in all games, but the exact amount depends on the game and the type of bet placed. In games such as poker, the house takes a commission on bets called rake.

Casinos are a source of revenue for many cities and states, especially in the United States. Some are privately owned, but a growing number are owned by hotel and restaurant chains. In the United States, the largest concentration of casinos is in Nevada, followed by Atlantic City and Chicago. Casinos are also found on some American Indian reservations, where state laws do not prohibit them.