Lottery is a game in which players have the opportunity to win a prize based on random chance. The prize money can range from a single item to the entire prize pool. The odds of winning a lottery prize are determined by the number of tickets purchased and the number of matching numbers on each ticket. In the event of multiple winners, the prize is divided equally among the holders of the tickets.

The casting of lots to make decisions and determine fates has a long record in human history (and a mention in the Bible), but the use of lotteries for material gain is much more recent, dating back to the Low Countries in the 15th century, where lottery games were used to raise funds for town fortifications and help the poor. Regardless of the history behind the practice, lotteries have become widespread throughout the world and continue to grow in popularity.

Whether they are state-run or privately run, all lotteries work on the same basic principles. A government or private corporation establishes a monopoly for the games; designs and markets its games; sets its prizes; and, after initial success, continues to expand in size and complexity as pressure mounts for additional revenues. This expansion has fueled criticism of lotteries, ranging from their perceived regressive impact on lower-income individuals to the likelihood that they increase opportunities for problem gambling. But it also has fueled the evolution of the lottery, making it a more complex and dynamic industry.