A casino (also known as a gambling house or a gaming hall) is an establishment for certain types of gambling. Casinos are often located near or combined with hotels, restaurants, retail shopping, cruise ships and other tourist attractions. They also serve as meeting places for many business and social organizations. The modern casino is like an indoor amusement park for adults, with the majority of its entertainment (and profits for the owner) coming from games of chance. Slot machines, blackjack, roulette, craps, keno and other games provide the billions of dollars in profits casinos make every year.

Besides offering games of chance, casinos also focus on customer service and offer perks to lure in gamblers. For example, a player might be rewarded with free hotel rooms or buffets depending on how much he or she spends at the casino. These perks are known as comps. During the 1970s casinos in Las Vegas offered heavily discounted travel packages and free show tickets to attract as many people as possible, since they knew that this would increase their gambling revenue.

In the early days of the casino industry, legitimate businessmen were reluctant to get involved because they saw it as a shady endeavor with a notorious reputation. As a result, several casinos were funded by organized crime figures who had ample cash from drug dealing, extortion and other illegal activities. The mobsters not only provided the money to open and operate the casinos, they became intimately involved in running them and even took sole or partial ownership of some of them.