A casino is a gambling establishment where people play a variety of games against the house. Some of these games are table games conducted by croupiers, such as blackjack and roulette; others may be slot machines or electronic games that use random numbers for payouts. The casino profits from the difference between the amount of money a patron wagers and the expected return on those bets, known as the house edge. In addition, casinos earn money through a percentage of the rake from poker and similar card games.

As disposable income increases around the world, so too do the popularity of casinos. In the United States, for instance, there are more than 1,000 casinos, from the glittering Las Vegas Strip to the smoky pai gow parlors of New York City’s Chinatown. Each has its own style and personality, but there are a few things all of them have in common.

One is location: Casinos are built near major tourist attractions to draw gamblers from the surrounding area and thereby boost local economies. They are also built to be accessible, with shuttle buses crammed with tourists running 24 hours a day and jet airliners flying in every direction.

Another common feature is security: Casinos employ a variety of technology to prevent cheating and other crimes. For example, they monitor the movement of players through one-way glass at tables and slot machines, and they have catwalks in the ceiling that allow security personnel to see the floor through a lens. Moreover, sophisticated electronic systems such as “chip tracking” enable casinos to oversee the amount of money wagered minute by minute and quickly detect any statistical anomalies; while roulette wheels are electronically monitored to ensure they’re always spinning true.