A casino is a place where people can play a variety of games of chance for money. Often, the casinos also offer restaurants and free drinks. They also usually feature stage shows and dramatic scenery to attract players. Gambling probably predates recorded history, with primitive protodice and carved six-sided dice found in archaeological sites. But the modern casino as an institution for gambling first developed in the 16th century. At that time, European aristocrats often gathered in private places called ridotti to play games of chance and other pastimes.
The main way that casinos make money is by taking a small percentage of each bet placed on their tables. This is called the house edge and can vary from game to game. Some games have lower edges than others, but the overall edge for each table is a constant (and not very large).
Casinos use technology to keep an eye on their tables and patrons. For example, chips with built-in microcircuitry enable the casino to monitor the exact amount of money being wagered minute by minute and to quickly discover any anomaly; automated roulette wheels are constantly monitored electronically for statistical deviations from their expected results.
Casinos employ many employees to oversee their games and protect their profits. Dealers are trained to spot blatant cheating such as palming, marking or switching cards and dice; pit bosses and table managers watch over table games with a more sweeping view, looking for betting patterns that may indicate cheating. Casinos also monitor their games using computer programs to determine the odds and payouts for each machine. These programs are sometimes referred to as casino management systems.