The unofficial but common term "Third World" refers to the world's less wealthy and less developed countries. In the decades after World War II, the term was developed in recognition of the fact that these countries were emerging from colonial control and were prepared to play an independent role in world affairs. In academic discussions of the world as a single, dynamic system, or world systems theory, the term distinguishes smaller, nonaligned countries from powerful capitalist countries (the First World) and from the now disintegrating communist bloc (the Second World). In more recent usage, the term has come to designate the world's less developed countries that are understood to share a number of characteristics, including low levels of industrial activity, low per capita income and literacy rates, and relatively poor health care that leads to high infant mortality rates and short life expectancies. Often these conditions accompany inequitable distribution of land, wealth, and political power and an economy highly dependent on exploitation of natural resources.