A casino is an establishment for certain types of gambling. Casinos are often built near or combined with hotels, restaurants, retail shops, and other entertainment facilities. They may also be located on cruise ships or other tourist destinations. Most casinos are regulated and have high security measures. The United States is home to the most casinos, with Nevada and New Jersey having the highest concentrations.

Casinos use a variety of techniques to attract and keep gamblers. For example, they often feature bright and sometimes gaudy floor and wall coverings that stimulate the senses and create an exciting atmosphere. The sounds of clanging coins, bells, and whistles are constant, and waiters offer free drinks (alcoholic and nonalcoholic). Casinos are also designed around the sense of sight, with a wide array of colors and lighting to appeal to human visual cues.

Something about gambling seems to encourage people to cheat and steal, which is why casinos spend so much time, money, and energy on security. They employ many people to watch over the games and the patrons, and they use technology to help prevent cheating and stealing. For example, a special type of casino game called roulette has a computerized system that monitors the wheel and alerts the casinos to any deviation from the expected results. Casinos also use video cameras to observe the action from all angles, and they have employees who supervise the players and tables to make sure that everyone is playing by the rules.