A lottery is a form of gambling in which numbers are drawn at random to determine a winner. The winnings may be cash, prizes, services or real estate. The probability of winning the lottery is very low, but it can be fun to play. The history of lotteries dates back to ancient times, and they continue to be popular today.

Despite their ubiquity, lotteries are controversial. They raise questions about the morality of promoting gambling and its impact on society. Lotteries also attract criticism for supposedly preying on the poor, and they are often criticized for the high cost of promotion and advertising. Nonetheless, the popularity of lotteries has remained consistent, even in states with relatively good fiscal health.

Many state governments use the lottery to promote public services and stimulate economic growth. They establish a monopoly for the lottery by statute and create an agency or corporation to run it (as opposed to licensing a private firm in return for a share of the profits). In most cases, the new lottery begins operations with a modest number of relatively simple games. The steady demand for additional revenues, however, drives the lottery to progressively expand its offerings and the number of players.

Ultimately, the lottery is a classic example of policymaking done piecemeal and incrementally, with little general oversight or evaluation. Thus, the initial decisions about whether to adopt a lottery and its structure are soon overtaken by the continuing evolution of the industry, and state officials find themselves operating at cross-purposes with the larger public interest.