A system in which people buy numbered tickets and winners are chosen by chance, often sponsored by states or organizations.
The practice of drawing lots to decide ownership or other rights is recorded in ancient documents and was common in Europe during the fifteenth and sixteenth centuries. In the United States state lotteries are run by governments that have granted themselves monopoly status in their operation, limiting competition from private companies. The resulting profits are often used to fund public works projects and other programs.
Large prizes attract the attention of the media and the public, which helps drive lottery sales. But when those prizes are very large, the actual odds of winning are extremely small. People still enter the lottery, not because they believe they will win, but because there is a sliver of hope—along with that meritocratic belief that somebody, someday, is going to get rich.
Many, but not all, states provide information about lottery results after a lottery has closed. This data can be useful for understanding how well a lottery is distributing its prize money.
A common measure of how unbiased a lottery is is to look at the number of times an application has received a certain position in the results. In the example shown in the figure below, each row is an application and each column represents a lottery result (from first on the left to one hundredth on the right). The fact that the columns are colored in a similar way indicates that the lottery is distributing its prizes fairly.