A lottery is a form of gambling in which tickets are drawn at random for prizes. Some governments outlaw lotteries, while others endorse them and organize state or national lotteries. State-sponsored lotteries are the most common type, but they also exist in private organizations. Many people buy lottery tickets as low-risk investments. However, purchasing a ticket can cost an average person thousands of dollars in foregone savings for retirement or college tuition. It’s important to understand how lottery games work before investing in one.

In the United States, lotteries are regulated by state law and generally require that winners be 18 years of age or older. State laws also establish lottery commissions to administer the lotteries. The commissions typically select and license retailers, train employees of retail outlets to use lottery terminals and sell tickets, promote the lottery and its games to potential players, and oversee a variety of other administrative functions.

The history of lotteries is long and varied. Although the casting of lots to determine fates has a long record in human history (including several instances in the Bible), lotteries in their modern sense began with public games organized in the 15th century in the Low Countries for town repairs and the benefit of the poor.

When a state decides to introduce a lottery, it legislates a state monopoly and a public agency or corporation to run the lottery (as opposed to licensing a private firm in return for a cut of the profits). In general, the agencies begin operations with a small number of fairly simple games, but over time they expand their product line to include new games and increase promotional spending.