The Casino industry rakes in billions of dollars each year for the companies, investors, and Native American tribes that own and operate them. State and local governments also reap substantial revenue from taxes and fees paid by casino patrons.

Many people associate casinos with the glitz and glamour of Las Vegas, but casino gambling is found worldwide in a wide variety of sizes and types. Some casinos are small, family-owned establishments; others are part of large resorts or entertainment complexes. Many American casinos rely on high-volume, low-edge games such as slot machines and video poker to generate income. Other casino revenue streams include table games such as roulette, craps, and blackjack; sports wagering; and keno.

According to a survey conducted by Gemini Research, a Nevada-based consulting firm, in March 2002, a majority of casino gamblers favored slot machines, with 30% choosing card games and 23% preferring table games such as poker and blackjack. Other popular choices included baccarat, pai gow poker, and bingo. The most lucrative gamblers are those who place large bets—in the tens of thousands of dollars—on high-risk games such as craps and roulette, for which casinos have mathematical expectations of winning only a small percentage of the total amount wagered. High rollers are courted by casinos with lavish inducements such as free spectacular entertainment, limousines, hotel rooms, and fine dining.

The federal government classifies casinos under NAICS code 713210. Other gaming establishments, such as racetracks and racinos, are classified under NAICS code 721120.