A casino is a place where people gamble through games of chance. These include slot machines, roulette, blackjack, baccarat, craps and poker. Some casinos also have entertainment shows and restaurants. Casinos can be found in cities, towns, and even islands. Some are operated by governments while others are private enterprises. Most casinos require patrons to be 21 or older and to have valid identification. Some states limit the number of times a person can visit a casino in a given period.
The idea of gambling probably predates written history, with primitive protodice (cut knuckle bones) and carved six-sided dice found at archaeological sites [Source: Schwartz]. However, the casino as a place where a variety of gambling activities can be found under one roof did not develop until the 16th century. This was during a time when a gambling craze swept Europe and wealthy Italian aristocrats would hold private parties in places known as ridotti.
Casinos earn money by giving their customers a mathematical advantage on each game played. This can be as small as two percent, but it can add up over the millions of bets made in a single day. The advantage is called the house edge or vig. The casino may also take a commission on certain games such as poker, where players play against each other, called the rake.
Casinos spend a lot of money on security. Besides hiring trained personnel to keep watch, they have high-tech surveillance systems that provide a virtual “eye in the sky” for the entire building. The cameras constantly monitor everything, and they can be adjusted to focus on suspicious patrons. The patterns and routines of the games themselves make it easy for security to spot unusual activity.