Urbanization is the term given to describe the shift of population from rural to urban areas. The growth of industry from the late 18th century onwards, led to migration on a large scale and the rapid growth of cities, some of which were previously small towns or villages. This process began first in Britain, followed by the rest of Europe and North America. Cities during this period of expansion were overcrowded and unhealthy places to live in, where thousands regularly died from diseases spread by contaminated water or the appalling, cramped living conditions. Nevertheless, in countries such as the USA, over the course of the 20th century the urbanization rate increased from around to 40% to 80%.

Developing countries

By the end of the 20th century, urbanization had slowed in the developed world, but was rapidly increasing in the developing world—and continues to do so. An important milestone was passed in 2007, when, according to the United Nations, for the first time, more than half the world's total population were recorded as living in cities.

​​​​​​​The UN has also predicted that by 2050 about 68% of the entire developing world will be urbanized. Most of this growth will occur in Africa and Asia. Today, in Asia the urban agglomerations (built-up areas together with suburbs) of, for example, Delhi, Jakarta, Karachi, Manila and Mumbai, are each already home to more than 20 million people.

Why move to the city?

Many people move from the countryside to cities either to earn more money, or, especially in the case of women, to seek opportunities (e.g. education and employment) not available in rural areas. But, especially in China and India, people are made to leave their villages for other reasons: the acquisition of farmland by governments or businesses for development or intensive agriculture forces peasants off their land with nowhere else to go; in times of flood or famine, fleeing to the city is a matter of survival; or simply because farm work is tough and unrewarding.

Shantytowns

Many developing countries are unable to provide either sufficient jobs or adequate housing for the huge numbers of rural migrants. Unplanned migration in developing countries contributes to severe overcrowding and the growth of slums. Shantytowns are commonly found on the edges of cities in Latin America, Africa, the Indian subcontinent and Southeast Asia. They have mushroomed as people build their own homes, constructing shelters and shacks from any material that comes to hand. People who live in shantytowns often cannot find work or are forced to work for very low wages.

Urbanization in China

In China, urbanization is a process planned and managed by the government, a key element in its overall strategy to develop its economy to the maximum. Cities such as Beijing, Shanghai, Hong Kong, Guangzhou and more recently Shenzhen have all expanded hugely since the 1990s as part of China’s bid to create “global cities” (cities that are considered important hubs for finance and trade in the global economy) on the same level as, say, New York, Tokyo and London.
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