A casino is a place where gambling takes place. While some casinos add a few luxuries like restaurants, free drinks and stage shows to help lure gamblers, it is still basically a place where people can wager money and hope that their luck holds up.
While the casinos are often built on the premise of chance, they do make money through certain fees and percentages. For example, in games of skill (like poker), players bet against each other and the house takes a small commission on each bet, which is called the rake or vigorish. Similarly, slot machines and video poker have built in percentage of expected value that the house has over the player. The vig or rake can vary depending on the game and the payouts set by the casino.
The casinos also spend a lot of money on security to make sure no one cheats or steals their way to a jackpot. This starts on the floor, where dealers keep a close eye on everyone to ensure that no one is palming or marking cards or switching dice. In addition, pit bosses and table managers watch over the patrons with a more sweeping view of betting patterns that could indicate cheating or collusion. Lastly, casinos often remove all indicators of time like clocks and menus so that players stay lost in play for as long as possible. The more they lose their sense of time, the more likely they are to spend.