In politics, humanitarian aid, and social science, hunger is a condition in which a person, for a sustained period, is unable to eat sufficient food to meet basic nutritional needs.

Throughout history, portions of the world's population have often experienced sustained periods of hunger. In many cases, this resulted from food supply disruptions caused by war, plagues, or adverse weather. For the first few decades after World War II, technological progress and enhanced political cooperation suggested it might be possible to substantially reduce the number of people suffering from hunger. While progress was uneven, by 2000 the threat of extreme hunger subsided for many of the world's people.