The urbanization process is directly related to the increase of the urban population in relation to the rural population. Therefore, when the population of a given place exceeds 50% of the total inhabitants, we say that this space is urbanized.
By 1800, only 3% of the population was in the urban area. But since the 1st Industrial Revolution, the movement of the population from the countryside to the cities in search of employment increased. They functioned as repelling factors of the rural area: low agricultural wages, land concentration and mechanization of the countryside.
By the mid-nineteenth century, during the 2nd Industrial Revolution, about 15 percent of the world's population was already living in cities. In urban centers the factors of attraction were not just the process of industrialization but also the expansion of the service sector.