Terms linked to the concept developed country include "advanced country", "industrialized country", "'more developed country" (MDC), "more economically developed country" (MEDC), "Global North country", "first world country", and "post-industrial country". The term industrialized country may be somewhat ambiguous, as industrialisation is an ongoing process that is hard to define. The first industrialized country was the United Kingdom, followed by Belgium. Later it spread further to Germany, United States, France and other Western European countries. According to some economists such as Jeffrey Sachs, however, the current divide between the developed and developing world is largely a phenomenon of the 20th century.. Mathis Wackernagel calls the binary labeling of countries as "neither descriptive nor explanatory. It is merely a thoughtless and destructive endorsement of GDP fetish. In reality, there are not two types of countries, but over 200 different countries, all faced with the same laws of nature, yet each with unique features."