Lottery is a fixture in American society — people spend upward of $100 billion per year on tickets. Whether that money has any meaningful impact on state budgets or is worth the trade-offs to people who lose it, though, is up for debate.

The word lottery likely comes from Middle Dutch Loterie, which itself might have been a calque on Middle French loterie, meaning “the action of drawing lots” (from the root lotte, to draw). The first recorded lotteries were held in the Low Countries in the 15th century, and they were used to raise money for towns, town fortifications, and charity. They were popular and hailed as a painless form of taxation.

There are a variety of types of lotteries, from scratch-off cards to multi-million dollar jackpot games. In all lotteries, there are two basic elements: 1) a pool of applications and 2) a method for selecting winners. Applications can be bought individually or in multiples, and they can be purchased either through a central lottery organization or through sales agents. In addition, there is usually a way for applicants to track their purchases and application status.

For a quick lesson in probability, try buying a few scratch-off lottery tickets and chart the “random” outside numbers that repeat. Look for digits that appear more than once, and pay special attention to the ones that occur only once. These are called singletons, and they indicate a winning card 60-90% of the time.