A lottery is a form of gambling. It involves selecting a set of numbers and hoping to match them in order to win a prize. Although it is a game of chance, it is regulated by some governments and is therefore legal.

Lotteries have been around for thousands of years. During the Roman Empire, for example, emperors organized lotteries to raise money for repairs of the city. They also used them to finance canals, bridges, and fortifications.

In the early days, the lottery was viewed as a way to provide relief to the poor. It was also used by several colonies to finance local militias.

The first known European lottery was held during the Roman Empire. Several wealthy noblemen distributed tickets at Saturnalian revels. During the Middle Ages, lotteries were used by governments to fund fortifications, roads, libraries, and college tuition.

After World War II, most forms of gambling were banned in most countries. However, some governments endorse or support lotteries.

Today, most states in the United States allow online lotteries. However, some of them are regulated and some are outlawed. Some of the most popular games include the Powerball and Mega Millions. While the odds of winning are low, the prize amount can be enormous.

A few online lotteries are now offering a new service called Instant Games. These allow players to play through the internet or a mobile app. Using an e-Instant, players can choose a single number, wager, and check their results.