Around two-thirds of the world’s population live in the so-called Third World. This term refers to all nations in Africa, Asia, South and Central America, the Caribbean and Oceania that are underdeveloped.
The term “Third World” was introduced during the period of the Cold War, when two military blocs stood opposing one another. One bloc (the “First World” – that is how the democratic industrial nations were named) were led by the USA. The other was the communist bloc led by the Soviet Union (the socialist industrial nations, the “Second World”). The First and Second Worlds ended with the collapse of the Soviet Union in 1991. The name “Third World” is barely used any more these days. Instead, people speak of “developing countries”. Occasionally you will hear the term “Fourth World” used for the very poorest countries that would not be able to survive without foreign assistance.