Gambling is a complicated activity, requiring careful calculation of risk and reward, wise decisions and a little luck. It’s a world of glitz and glamour but also seediness and grit.

Traditionally, casinos have been large places where patrons can play games of chance or skill. While modern casinos have added restaurants, free drinks, stage shows and dramatic scenery, they are still primarily gambling establishments.

Casinos make money by charging a small percentage of bets to players, known as the vig or rake. The amount is usually lower than two percent but adds up over the millions of bets placed in a single casino. This enables them to build flamboyant hotels, elaborate fountains, giant pyramids and towers, and replicas of famous landmarks.

Modern casinos have sophisticated security measures that start on the gaming floor. Dealers keep their eyes focused on their own game and can easily spot blatant cheating. Pit bosses and table managers have a broader view of the tables, noting betting patterns that might indicate fraud or stealing. Casinos also have cameras in the ceiling that give them an eye-in-the-sky perspective and can be adjusted to focus on suspicious patrons.

Casinos are often choosy about their high rollers, giving them free rooms and food as well as tickets to shows. These players can generate tens of thousands of dollars in profits for the casinos. They are watched carefully by a team of people who can spot unusual behavior, from hand signals to erratic betting patterns.