A lottery is a form of gambling in which numbers are drawn to determine the winner. Prizes may be cash or goods, and some states use the lottery as a way to raise money for public purposes. Lotteries have a long history, although the modern form of the lottery is relatively recent. In the United States, there are state-regulated lotteries and private commercial games that offer prizes such as cruises or sports tickets. There are also many online and independent lotteries.

Generally, people buy lottery tickets because they expect to receive a positive net utility from doing so. If the ticket price is low enough, the disutility of a monetary loss will be outweighed by the expected utility of entertainment and other non-monetary benefits. If the ticket price is very high, however, the expected net utility will be less than zero.

The earliest recorded lotteries were held in the Low Countries in the 15th century, for a variety of purposes, such as building town fortifications or helping the poor. Benjamin Franklin sponsored a lottery during the American Revolution to raise funds for cannons to defend Philadelphia against British forces, but it was unsuccessful.

In most modern lotteries, players can choose their own numbers or let a computer select them for them. Those who choose their own numbers tend to pick numbers based on personal information, like birthdays or home addresses, rather than purely random numbers. As a result, the winnings of such people are likely to be smaller than those of people who choose random numbers.