Casinos are entertainment venues that offer a variety of gambling activities. They often feature bright and gaudy floor and wall coverings, and are designed around noise, light, and excitement. Many casinos serve alcohol at reasonable prices, and food is available in some. In 2008, 24% of Americans reported having visited a casino. The most common casino games are blackjack, roulette, craps, and poker. Some casinos specialize in far Eastern games such as sic bo, fan-tan, and pai gow, while others offer more traditional table games like two-up, banca francesa, and boule.

Casino gambling attracts a diverse group of gamblers. According to a 2005 study by the Roper Reports GfK NOP and TNS, the typical casino patron was a forty-six-year-old female from a household with above-average income. This age group made up the largest percentage of gamblers in both land-based and online casinos.

A major source of revenue for casinos is the rake, a fee or commission taken by a dealer from each bet in card games such as baccarat and poker. The house also takes a cut of the action in slot machines. The rake is typically the main source of profit for a casino, although some offer other incentives such as comps (free merchandise or services).

Although they are not required to do so by law, most casinos provide elaborate security systems. They usually employ a physical security force to patrol the premises and respond to calls for help or reports of suspicious or definite criminal activity, as well as a specialized surveillance department that operates closed circuit television monitors called an eye-in-the-sky. These are usually placed at every table, window, and doorway of the casino, and can be focused to watch particular tables or suspicious patrons.