The Casino () is a building or room where gambling games are played. Casinos often have many games that can be categorized as table games, slot machines or electronic gaming machines, and they are usually operated by a centralized management and staff.

The casino industry is regulated by laws that differ from state to state. Some jurisdictions allow local governments to run casinos, while others prohibit them entirely or restrict their growth. Some states, such as Oklahoma, have large casinos that rival those in Las Vegas.

While gambling in the United States is generally legal, most states limit the number of casinos to prevent addiction. Most states also require casinos to monitor the activities of their patrons, provide help to those who need it and prohibit loitering. Several states also require that casinos be separated from other businesses to prevent conflicts of interest.

In the United States, the most popular casino game is poker. The largest casinos have more than 1,000 tables. The casinos are usually built in cities with a large tourist population, such as Las Vegas.

Gambling was illegal for most of the nation’s history, although it still occurred in some places openly and with the complicity of local law enforcement. It was only after World War II that state officials began to legalize casinos, and it took decades for them to become established outside of Atlantic City and Nevada. Modern-day casino marketing has grown to include a variety of promotional strategies. These include direct mail, newspaper ads, billboards and street posters, consumer shows (like trade shows) and sponsorship of high profile endorsers like former professional athletes and actors.