A casino is a gambling establishment where patrons can gamble by playing games of chance, or with some skill (such as blackjack or video poker). Most casinos feature restaurants, bars, and hotels. Some of the largest casinos are enormous entertainment complexes with thousands of slots and table games. Others are small and intimate, with only a few tables and fewer than 100 slot machines.

Casinos are regulated by state and local laws, as well as the federal government. They are often criticized for their negative impact on communities, due to the drain of money from the local economy, and the cost of treating problem gambling. In addition, the jobs of casino employees are frequently replaced by cheaper labor from abroad.

There is also the possibility that casino employees and patrons may cheat and steal, either colluding or acting independently. Security is a major issue in many casinos, and modern ones are heavily automated with electronic monitoring systems. For example, chip tracking uses built-in microcircuitry to monitor the amount of money wagered on each game, and roulette wheels are electronically monitored for any statistical deviation from expected results. In addition, high-tech “eye-in-the-sky” cameras in the ceiling enable surveillance personnel to watch every table, window, and doorway, and can be directed to focus on suspicious patrons by security workers in a separate room filled with banks of monitors.

The first casinos were operated by gangsters, but with the advent of real estate investors and hotel chains in the 1930s, they began to attract legitimate businesspeople. By the 1990s, several American states had legalized casino gambling, and many casinos opened on Indian reservations, which are not subject to state antigambling statutes.