Official lottery, or state-run gambling operations, offer tickets with a chance of winning a prize in exchange for a payment. Some governments outlaw them, while others endorse them to the extent of organizing a national or state lottery. In modern times, most governments regulate the game by prohibiting sales to minors and licensing vendors to sell them. In addition to the traditional lotto, most states now offer games such as instant tickets, keno and video lottery terminals.

Lottery games have a long history, starting in the 15th century in the Low Countries with a series of public lotteries for town fortifications and to help poor people. In colonial America, private and public lotteries played a significant role in raising funds for roads, canals, churches, schools, colleges and other public uses. Some of the country’s oldest universities, such as Columbia and Princeton, were founded by lotteries. At the outset of the Revolutionary War, the Continental Congress established a lottery to raise money for the army.

In the United States, there are now 45 state-operated lotteries, plus the District of Columbia and Puerto Rico. A large number of cities also run local lotteries. Although the vast majority of state-run lotteries have preprinted numbers or symbols on the ticket, a growing number use a random selection process to choose winners. The latter type of lotteries has gained popularity in recent years. A common feature of these lotteries is that a percentage of the proceeds are deducted as organizational and promotion costs, and some goes as taxes and profits to the sponsor. The rest is distributed as prizes.