A casino, also known as a gambling house or a gaming establishment, is a building or room where people can gamble. Its size and scope can vary significantly. Some casinos are large, sprawling complexes modeled after Las Vegas, complete with entertainment venues and restaurants. Others are smaller, standalone buildings or rooms that offer a more limited selection of gambling activities.

Most games played in casinos involve chance, but a small number of them have a skill element. Most of these games have mathematically determined odds that ensure the house has a long-term advantage over the players, which is sometimes referred to as the “house edge”. Casinos also earn money from non-gambling activities, such as a commission on poker tournament winnings, or by giving out complimentary items (complimentary comps).

In many countries, casinos are operated by government-licensed operators. In some cases, the casinos are owned by private businesses. In the United States, the casinos are usually located on Indian reservations and are not subject to state antigambling laws. Several states have legalized casinos on riverboats, and the industry is growing in other countries such as South America.

When most Americans think of a casino, they picture the Las Vegas Strip, with its giant hotels and entertainment venues. However, the concept of a casino is more widespread than this. For example, the elegant spa town of Baden-Baden in Germany once hosted a casino that attracted royalty and European aristocracy, and the first modern casinos appeared in Europe after World War II.