Lottery is a form of gambling in which players buy tickets for the chance to win a prize, normally money. The winner is chosen at random. Lotteries are common in the United States, but they have a long history in many other countries. The casting of lots to decide decisions and fates has a long history, with several instances recorded in the Bible. Modern lotteries are typically state-run, and the winnings are used to fund public services or to promote charitable causes.

To determine the winners, the tickets are thoroughly mixed by some mechanical means, such as shaking or tossing. The resulting pool is then scanned or sorted for the winning numbers or symbols, usually with the help of a computer. The lottery operator then publishes the results and distributes the prizes. The purchase of lottery tickets cannot be accounted for by decision models that use expected value maximization, as the cost of the ticket exceeds the likely winnings. However, people still purchase tickets for entertainment and fantasy values, or because they enjoy the excitement and adventure of becoming rich.

Moreover, the costs of organizing and promoting the lottery must be deducted from the total prize pool, leaving the remaining sum for the winners. In addition, a percentage of the prize funds is typically taken by retailers as commissions and a portion goes as profit to the lottery operator or sponsor. These deductions reduce the size of the prizes and may influence the preference for large or small prizes. Nevertheless, the popularity of lotteries seems to be related to an inextricable human tendency to gamble and imagine themselves as heirs to fortunes. This is especially true of lower-income individuals, who are disproportionately represented in the population of lottery players.