A lottery is a form of gambling in which numbers are drawn for prizes. It is popular in many countries, including the United States. Lotteries are often used to fund public projects, such as highways and schools. The odds of winning a lottery are low, but the prizes can be large. A lottery is often run by state governments, but there are also private lotteries and international lotteries.

A person can win a lottery by purchasing a ticket and matching the numbers that are randomly selected in the drawing. The prize money may be cash or goods or services. In the United States, the National Lottery Commission regulates state-sponsored lotteries and oversees the distribution of prizes. The most common lottery games include the Powerball, Mega Millions and Florida Lotto.

Although the casting of lots to decide matters has a long history (and is mentioned several times in the Bible), modern lotteries were established by public law in the 18th century. They are based on the theory that everyone would be willing to risk a trifling sum for a chance at considerable gain, and that people prefer a small chance of gaining much to a large chance of gaining little.

Historically, the development of lotteries in a given state has followed similar patterns: a legislature legislates a monopoly for itself; it establishes a state agency or public corporation to run the lottery (as opposed to licensing a private firm in return for a share of the profits); it begins operations with a modest number of relatively simple games; and, as revenues grow, it progressively expands its operation by adding new games, including keno and video poker.