• Urbanization refers to the population shift from rural to urban areas. The process of urbanization affects all sizes of settlements, so villages gradually grow to become small towns, smaller towns become larger towns, and large towns become cities. This trend has led to the growth of mega-cities.
• The concept of urbanization is closely related to modernization, industrialization and the sociological process of rationalization. It is relevant in the study of geography, sociology, economics, urban planning and public health. Urbanization changes in the number of population that led to other changes in land use, economic activity and culture.
• Urbanization provides an opportunity for sustainability with the efficient utilization of resources. For example, protecting the biodiversity of natural ecosystems and creating more sustainable land use.
• Industrialization is a major cause of urbanization. After industrial revolution, cities become more important centres for commerce and production.
• Opportunities for employment in new emerging industries and factories are one of the important reasons for urbanization.
• Increased development of new building or infrastructure of towns and cities as well as convenient facilities such as, roads, bridges, construction, schools and hospitals were made available to the increasing population.
• Good health care and close proximity of hospitals for the city dwellers is also enhancing the pace of accelerator of urbanization rather than the countryside where fewer doctors and medical facilities are available.
• Commerce and trade play a major role in urbanization. The distribution of goods and services and commercial transactions in the modern era has developed modern marketing institutions and exchange methods.
• Transportation and communication is another reason for urbanization. Industries depend on transportation as the raw materials and manufactured goods can be transferred in large volume. Communication facilities such as telephones, telegraph, computer, wireless and postal services, etc., are usually available in urban centers.
• Urban areas are characterized by sophisticated technology better infrastructure, communication, medical facilities, etc.
• Over population is a major problem of cities. Intensive urban growth can lead to greater poverty. It has resulted in accommodation problem, growth of slums etc. Urban life is highly monotonous. The concept of neighbourhood, community life are almost absent in cities.
• Over-dependence on large number of vehicles and burning of coal to supply energy causes air pollution.
a. Water pollution results from poor sewage and disposal of industrial wastes into waterways.
b. Traffic congestion and noise pollution are the major environmental impacts of large cities.
c. Waste management is a major problem in large cities. Large volumes of uncollected waste create multiple health hazards.
• Satellite cities are the planned and smaller cities that are located near to a large city or major metropolitan area. Satellite cities could be completely standalone cities, developed outside metros. They are self-containing and independent cities.
• A 'smart city' refers to an urban region that is highly advanced in terms of overall infrastructure, sustainable real estate, communications and market capability.
• A 'smart city' refers to an urban region that is highly advanced in terms of overall infrastructure, sustainable real estate, communications and market capability such as, Seoul in South Korea (World) and Bhubaneswar in Odisha (India).