1- SOCIO-DEMOGRAPHIC REVOLUTION
Undoubtedly the area that reflects, in the most drastic way, the quickness of changes that occurred in the course of the twentieth century is that of demographic, particularly the growth of the human population.
From the origin of humanity to the early (beginning of the) twentieth century, thisgrowth has been restructured thanks to the significant demographic work. Very slow in the Paleolithic when humanity was essentially amassers- hunters – fishermen, the demographic growth (of the world population)occurred(happened) under auspicious (more favorable) terms to the Neolithic with the advent of agriculture and the first cities (settlement).
Yet human societies are still very vulnerable to disease and nefaste (negate) natural environment. Thus, at the beginning of our era, the world population would be around 250 million inhabitants. At the end of the first millennium of our era, it was estimated at about 300 million people. It is not until the early nineteenth century that the world population reaches 1 billion (around 1800).
From the early nineteenth century, the industrial revolution era in Europe, the population (demographic) growth speeds(speeded) up. In the early twentieth century, in 1900, the world population is estimated at 1.613 billion people.This is already a significant (increase, burst) speed of population growth.
But this one became excessive with the demographic upsurge that humanity will live in the twentieth century. In