The lottery is a game in which people pay money to enter an event that randomly selects winners. The prizes range from cash to goods or services. People can choose their own numbers or use a machine to generate random selections for them. The prize amounts depend on how many tickets are sold and how long it takes before someone wins the jackpot. Prizes are sometimes split among multiple winners.

The casting of lots for decisions and fates has a long history in human history, although it was not until the 18th century that lotteries became popular for material gain. Benjamin Franklin sponsored a lottery to raise money for cannons to defend Philadelphia during the American Revolution. Other early lotteries included those that awarded subsidized housing units and kindergarten placements at reputable public schools.

Today, state lotteries are a major source of government revenues. They have a number of similarities: they are legislated as state monopolies; they establish a public agency or corporation to run them; they start with a modest number of relatively simple games; and, in an attempt to increase revenue, continually introduce new games.

Critics charge that lottery advertising is often deceptive, presenting inaccurate information about winning odds; inflating the value of money won (lotto jackpots are paid in equal annual installments over 20 years, with inflation and taxes dramatically eroding their current values); and persuading target groups to spend more than they would otherwise on a ticket, even if the expected gains from doing so are minimal. In this sense, they violate the principle of expected value maximization, which is a fundamental economic concept.