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Third World was a term originally used to distinguish nations that neither aligned with the West nor with the East during the Cold War, including many members of the Non-Aligned Movement. Today, however, the term is used to denote nations with a low UN Human Development Index (HDI), independent of their political status. Many "third world" countries are located in Africa, Latin America, and Asia. They are often nations that were colonized by another nation in the past. The populations of third world countries are generally very poor but with high birth rates. In general they are not as industrialized or technologically advanced as OECD countries. The majority of the countries in the world fit this classification. These countries are also known as the Global South, developing countries, least developed countries and the Majority World in academic circles. Development workers also call them the two-thirds world and The South. Some dislike the term developing countries as it may imply that economic development (industrialisation) is the only way forward, while they believe it is not necessarily the most beneficial. The term Third World is also disliked as it may imply the false notion that those countries are not a part of the global economic system. Some note that the underdevelopment of Africa, Asia and South America during the Cold War was influenced, or even caused by the Cold War economic, political, and military maneuverings of the most powerful nations of the time.
The term Fourth World is used by some writers to describe the poorest Third World countries, those which lack industrial infrastructure and the means to build it. More commonly, however, the term is used to describe either indigenous peoples or other oppressed minority groups within any country.
History of the term
The term "third world" was coined by economist Alfred Sauvy in an article in the French magazine L'Observateur of August 14, 1952. It was a deliberate reference to the "Third Estate" of the French Revolution. Tiers monde means third world in French, but in the sense of "one-third" -- it does not mean "third in rank" (which would be troisième monde). The term gained widespread popularity during the Cold War when many poorer nations adopted the category to describe themselves as neither being aligned with NATO or the Warsaw Pact, but instead composing a non-aligned "third world" (in this context, the term "First World" was generally understood to mean the United States and its allies in the Cold War, which would have made the East bloc the "Second World" by default; however, the latter term was very seldom actually used