A lottery is a game of chance in which winners are selected by a random drawing. Winners can win cash prizes, units in a subsidized housing block, kindergarten placements, or other goods and services. State lotteries typically have low odds and require participants to pay a small amount of money in exchange for the chance to win a large prize. Lotteries have a long history, and are used in a variety of decision-making situations, including sports team drafts and the allocation of scarce medical treatment. Critics claim that they promote addictive gambling behavior and serve as a regressive tax on lower-income groups.

Since its introduction in 1964, lottery has become an important source of public revenue in many states. Although its advocates have argued that it provides “painless” revenue—voters willingly spend money on a chance to win a little—it has generated controversy. In the past, critics have questioned whether it is appropriate for state governments to use lotteries to raise funds, and have accused them of being an unavoidable form of taxation. In the present, the popularity of lotteries has led to a wide variety of innovations that have transformed the industry. Before the 1970s, state lotteries were largely traditional raffles. People bought tickets in advance of a draw that would take place weeks or even months later. Lotteries are now a multibillion-dollar business that includes scratch-off tickets as well as games with smaller prizes. Revenues typically expand dramatically when a lottery is introduced, then level off or decline. As a result, state officials constantly introduce new games to maintain or increase revenues.