A casino is a place where people can gamble and play games of chance. It used to be that only large cities like Las Vegas were known for casinos, but now many smaller towns also have them, and even some smaller countries have them. Some are very glamorous and world-famous, like the Monte Carlo Casino in Monaco or the Baden-Baden Casino in Germany. Others are much less luxurious, but still very nice and popular with visitors.
Gambling in a casino is usually legal, although there are some restrictions on who can enter and how much money they can spend. The biggest casinos in the world can be staggeringly big, with beautiful decor and a mindblowing number of games. They often include hotels, restaurants, non-gambling game rooms, bars and swimming pools.
Most casinos have security in place to prevent cheating. This starts on the gaming floor, where dealers keep a close eye on their patrons and can spot blatant attempts to change the outcome of a game (palming or marking cards, for example). The shuffle and deal pattern of card games, the locations of betting spots in table games and the expected reactions of players all follow patterns that make it easier for security personnel to see when something is out of the ordinary.
Some casinos reward their best players with comps, or free goods and services. These can include meals, hotel stays, tickets to shows and even limo service or airline tickets. They are based on the amount of time and money spent at the casino, and can be very lucrative for the best players.