In the two and a half centuries since the Industrial Revolution in England, the process of industrialization has perhaps had more impact on all the nations of the world than any other complex set of forces. This process has not been uniformly introduced in all countries, nor has it occurred at the same time or at the same rate. Despite the common features of industrialization, these differences in its introduction and adoption have produced inequities among nations and among people on a scale never before experienced.

In describing various countries and regions of the world, certain terms have been adopted, first by official agencies such as the United Nations and national governments, and then more generally by scholars, journalists, and those interested in making sense of international relations. According to a now commonly used United Nations classification, more developed countries...