A casino is a place where gambling takes place. Although musical shows, shopping centers and lavish hotels help draw customers, casinos would not exist without games of chance such as blackjack, poker, craps and roulette. These games of chance have mathematically determined odds, giving the house an edge over the players. In addition to the house edge, the casino takes a percentage of the money that is gambled, called the rake or payout.
Many modern casinos focus on customer service and offer perks designed to encourage gamblers to spend more money. For example, some casinos use bright, sometimes gaudy floor and wall coverings that have a stimulating effect on the gamblers. Red is a popular color for these decorations, because it is believed to make gamblers lose track of time. In addition, some casinos have no clocks on their walls. Casinos also try to keep gamblers from leaving by offering them comps, or free goods and services. For example, during the 1970s Las Vegas casinos were famous for their deeply discounted travel packages and cheap buffets. Casinos also have catwalks in the ceiling that allow surveillance personnel to look directly down, through one way glass, on the gamblers at the tables and slot machines.
Some critics argue that casinos have a negative effect on the economy of their communities. They claim that they shift spending from other forms of entertainment and that the costs of treating problem gambling and lost productivity offset any economic benefits. Despite these criticisms, the casino industry continues to grow. By 2025 the global casino industry is projected to reach USD 126.3 billion.