From the flashing lights of Las Vegas to the illegal pai gow parlors in New York City, casinos are where people gamble and play games of chance. Some are enormous and lavish, with top-notch hotels, spas, restaurants and other amenities. Others are small and intimate. But whatever their size or location, they all make billions of dollars each year by taking bets from people who want to win at games of chance.

In the past, many casinos were run by mobster families and often involved organized crime. But as real estate investors and hotel chains began to see the money potential of casinos, they bought out the mobsters. The current generation of casino owners is much more choosy about who they let in. They focus on attracting “high rollers,” or people who spend a lot of money. High rollers are usually given special rooms where they can gamble in private. They also get a lot of comps, or complimentary items, such as free suites, meals and drinks.

Most casino games involve some element of skill, but the house always has a mathematical advantage. It is this edge, which is sometimes called the vig or the rake, that gives the casino its billions of dollars in profits each year. A casino game’s house edge can be as low as two percent or as high as 30 percent, depending on the rules of the particular game. Something about gambling (perhaps the presence of large amounts of money) seems to encourage some people to try to cheat, steal or scam their way to a jackpot. That’s why casinos spend a lot of time and money on security.