The official lottery is a state-sponsored gambling game where players purchase numbered tickets in exchange for the chance to win a prize. Prizes are typically cash but may also be goods or services. Unlike other forms of gambling, lotteries are managed at the state level and operated independently from federal oversight. However, two major national-level lottery programs have such a broad market presence that they serve as de facto national lotteries.

In the United States, a majority of state governments operate a lottery program. Lotteries are regulated by state law and are generally managed by an agency that includes a director and board. State laws define the rules of lotteries, including the minimum prize amount, the method for claiming prizes, and documentation a winner must present to claim a prize.

Governments that run lotteries are in the business of promoting gambling, and critics argue they impose a disproportionate burden on the poor. Nevertheless, lotteries are a popular source of revenue for many states and are not the only gambling options available to consumers.

Supporters of the lottery argue that it is a more equitable way to fund state programs than taxation, since no one is forced to buy a ticket and everyone can choose not to play. They further contend that it is a myth that people cannot control their gambling urges, and that limiting the number of games helps to reduce problem gambling. However, the lottery does not appear to have any effect on illegal gambling operations, and most studies find that it is not more effective than other forms of state revenue generation.