Gambling has been a form of entertainment since earliest recorded history. Dice have been found in ancient Egyptian tombs. As early as 2300 B.C., the Greeks, Romans, Chinese, and Japanese played games of skill and chance. Several games we play today have ancient origins. For example, the popular game of keno was played in China more than 2,000 years ago. The Chinese name for the game then was pak kop fiu, which means “white pigeon ticket.” Pigeons were trained to fly the tickets and winning numbers back and forth between the player and the lottery office. The game of blackjack (also known as “twenty-one”) has its roots in the 15th century. The French, Spanish, and Italians all had their own versions of this card game, though the total winning number was different for each country.

European colonists brought their gaming traditions to the American colonies. They played dice and card games, and they made bets when horses raced. Native Americans also had their own games of chance, including dice games and guessing games. Gambling was illegal for much of the early history of the United States (although illegal gambling was common). In 1869, Nevada attempted to control gambling within its borders by making it legal. The state permitted gambling for more than 40 years, from 1869 to 1910. A reform movement banned gambling for the next 21 years until 1931, when Nevada made casino gambling legal again.

In 1967 and 1969, Nevada passed Corporate Gaming Acts that removed restrictions on corporations having direct involvement in the casino industry. This began a trend toward corporate ownership of casinos. Today, many commercial casino companies are publicly held, and their stock is traded on the New York Stock Exchange and other financial exchanges.

In 1976, New Jersey became the second state to legalize casino gaming. Its first casino opened in 1978 in Atlantic City. Today, Atlantic City is the second-largest casino market in terms of annual revenue in the United States.

In 1988, the Indian Gaming Regulatory Act legalized gambling on federally recognized Native American reservations as a way to help Native Americans raise revenues to maintain economic independence. Today, there are 514 Native American gaming operations in 29 states. Indiana became the 29^th state to allow tribal casinos in 2018.

In 1989, the era of the destination casino resort dawned with the opening of the Mirage Hotel & Casino Resort in Las Vegas. At the time of its opening, the Mirage was the most expensive hotel casino in history, costing $630 million to build. During the past decades, many other casino corporations have built destination casinos in order to compete for customers. Also in 1989, Iowa and South Dakota legalized gaming, and during the next five years the gaming industry enjoyed the largest expansion into new jurisdictions in U.S. history.

In 1992, the first racetrack casino (known as a racino) opened in Rhode Island; its customers could play slot machines in addition to betting on the outcomes of dog races. By 1994, Delaware, Iowa, Louisiana, and West Virginia had also legalized racinos. Today, racetrack casinos are located in 14 states. 

In 1995, the American Gaming Association was founded to represent the professional interests of the commercial casino industry. It educates the public about the casino gaming industry and addresses federal legislative and regulatory issues such as Internet gambling and federal taxation. Its members include casinos and gaming equipment manufacturers, gaming associations, financial- and professional-services firms, and other gaming-related organizations.

In the early 2000s, online gaming became popular, although there was—and continues to be—great controversy about the legality of this type of gambling. In the United States, interstate online gaming is now prohibited, but U.S. consumers continue to place bets online with private offshore operators. Legislation supporting the legalization of Internet gambling has been introduced in the U.S. Congress. In 2013, the New Jersey state legislature made online gambling legal for residents of the state, while Delaware and Nevada also offered some legal forms of online gambling. Supporters hoped this would lead to increased tax revenues for the state. Opponents of legalized Internet gambling are concerned with the difficulty of controlling and regulating it.

In the past decade, mega-mergers of casino companies have become common. One example is the merger of Pinnacle Entertainment Inc. with Ameristar Casinos Inc. in 2012. Technology is also changing the industry. Some examples of new technology include ticket in/ticket out technology (which is eliminating the use of cash in slot machine playing areas), server-based games that allow operators to make changes to slot machines from a single computer server, radio frequency identification technology on casino chips that improves player tracking and security, and multiplayer games that allow players to compete against each other on a single game.