A casino (also known as a gambling hall) is a facility for playing games of chance. It also offers other entertainment activities such as shows and restaurants. The casino industry is regulated by law in many jurisdictions to ensure fair play and prevent criminal activity such as money laundering.

The exact origin of gambling is not fully understood, but it has been a part of human culture for millennia. Evidence of gambling has been found in China as early as 2300 BC, and the first modern casinos opened in Europe in the 1600s. Today, there are over 1,000 casinos worldwide. Many are located in cities with large populations, especially those with tourist attractions, such as Las Vegas and Atlantic City. Many other cities have casinos, but they are not as well-known.

Modern casinos have strict security measures to prevent cheating and stealing by patrons and staff, both in collusion and independently. Typical measures include security cameras, and the use of specialized employees to monitor and enforce gaming rules. Some casinos also offer complimentary items to gamblers, and some give a portion of their profits to charitable organizations.

Casino games vary by game, but all involve some element of luck and require the player to make a bet. The house edge is the mathematical advantage that the casino has over the players, and the variance is the amount of profit or loss that can be expected over time. These figures are calculated by mathematicians and computer programmers who specialize in gaming analysis.