Urban growth is one of the features of an industrial society. This process accelerated at the beginning of the 19th century and continued thereafter. The rapid growth of cities was caused, firstly, by overpopulation of the countryside due to improved land use and the introduction of advanced farming methods, as a result of which many hands were freed up. Secondly, the decline of small towns associated with the decline in handicraft production and small trade, as well as changes in transport: with the development of railway transport, the centers of industry moved to new areas.
Since the 20s. XIX century the mass migration of Europeans to other continents began. They left England, Germany, Scandinavian countries, Eastern and Southern Europe. They left for Latin America, Canada, Australia, New Zealand, South Africa, but most of the emigrants went to the United States.
Remember: The process of learning a person lasts a lifetime. The value of the same knowledge for different people may be different, it is determined by their individual characteristics and needs. Therefore, knowledge is always needed at any age and position.