A lottery is a game in which a person pays a small amount of money for the chance to win a large sum of money. The bettor normally writes his name or other symbol on a ticket that is deposited with the lottery organizer for subsequent shuffling and selection in a drawing. A varying percentage of the money staked is deducted for administrative costs and profits; the remainder is awarded to winners. The prizes may be cash or goods. Lottery games have been used as a form of public funding for numerous projects, including construction of cities and towns, assisting the poor, and military and civil defense.

A primary issue with lotteries is the question of whether they constitute a form of gambling that should be legalized, as some people argue, or not. Critics of lotteries point to evidence that they encourage addictive gambling behavior, are characterized as a regressive tax on lower-income groups, and often have a negative effect on society.

Lotteries have a long history, beginning in the Low Countries in the 15th century as a means of raising funds for town fortifications and charity. In America, Benjamin Franklin held a lottery to raise funds for cannons to defend Philadelphia during the Revolutionary War. Today, state lotteries offer a wide variety of games, with a major emphasis on instant products like scratch-off tickets and video games. They typically begin operations with a limited number of relatively simple games and then, due to pressure for increased revenues, add new ones at an ever-increasing rate.