Casino games have been around since the 17th century, but have always been controversial. This is because all games in casinos have a house edge, or house advantage, in favor of the house. The house edge varies among games, but blackjack and video poker have the lowest house edge and offer the best chance of winning. Despite this, the casino industry has made a lot of money over the years. Many studies have examined the effectiveness of casino games and the house edge. In 2013, the Wall Street Journal published a study revealing that only 13.5% of players win.

The house edge is the difference between the true odds and the payouts at a casino. The house edge varies by game type and is usually expressed as a percentage. A casino with a low house edge will make a mere 0.5% to 2% profit from every player, while a casino with a high house edge will make anywhere from fifteen to forty percent profit.

Modern casinos also implement elaborate security systems. They have cameras hanging from the ceiling and employees on the casino floor who keep an eye on the games and patrons. Dealers and pit bosses watch the table games to look for signs of cheating. They also have cameras that record video feeds for review later. Casino security systems have also been very effective in preventing crime.