A casino is a place where gambling is the primary activity. Although some casinos add a variety of amenities to attract gamblers — free food, stage shows and other distractions — they are technically just gambling houses.
In modern times, the most opulent casinos are usually resorts that combine hotels and entertainment. The casino at Monte Carlo, for example, is a huge complex that offers a wide range of entertainment and is the chief source of income for the principality of Monaco.
Gambling has long been a part of human culture. The precise origin is unknown, but evidence of gambling has been found in almost every civilization. In the modern world, there are numerous types of gambling, from horse racing and lottery games to video poker and blackjack.
Something about gambling (perhaps the presence of large sums of money) seems to encourage cheating, stealing and other forms of dishonesty. For that reason, casinos devote a great deal of time and money to security. Cameras are everywhere, and the casinos have elaborate systems that allow security personnel to monitor activities from a separate room full of banks of video screens.
To keep players gambling, the casinos offer a variety of incentives called comps. Historically, these perks were offered in the form of free buffets and show tickets. Nowadays, they are more sophisticated and focus on high rollers who spend a lot of money and generate a lot of profits for the casino. These players are given special rooms and get comps worth tens of thousands of dollars.