A competition based on chance, in which numbered tickets are sold and prizes (often money or goods) are awarded to the holders of those numbers. It is most often used as a means of raising money for a public project or charity. In the United States all lotteries are operated by state governments, which hold exclusive rights to this activity and use proceeds from it exclusively for government purposes. Lottery participation is widespread: as of 2004, most adult adults living in a lottery-operating state have purchased a ticket.

In colonial America, lotteries played a significant role in the financing of private and public ventures, including churches, colleges, canals, roads, and public-works projects. They were especially popular in towns with high levels of poverty, where residents could more easily afford to participate.

Today, most people who buy lottery tickets do so in retail stores, gas stations, restaurants and bars, and convenience and drugstores. Some retailers specialize in selling lottery tickets, and the number of outlets is larger than ever before. However, many low-income residents live in neighborhoods that do not have a large number of retailers selling lotteries.

Most people know that the odds of winning are long, but they continue to play because there is always this sliver of hope that the next draw will be their lucky one. These players also have a clear understanding that they will not increase their chances of winning by playing more frequently or by buying more tickets for a drawing, because each ticket has an independent probability that is not altered by the frequency of purchase or the number of other tickets bought.