Unit 1: What is a City?
The city is a part of our lives and our language: we might say, "I live in a city" or "I live near a city" or "I am moving to a city". We know what we mean when we make these statements because we have certain ideas about the city: the bright lights, the tall buildings, the traffic jams.
But, if asked, could we really define a city? Where would we draw its boundaries? How do we distinguish a city from a "town" or a "village"? There used to be a time when it was easy to identify a town or city. A town was a living space with a place of worship, like a Church, Mosque or Synagogue, a town square, a central market and a town hall. Many large cities were encircled by walls. But what about today when the old walls are no more than tourist attractions and every little settlement has a market and a town hall? How do we identify or define a city?
We can check the dictionary.
Going to the dictionary, however, does not help us be more precise in defining the physical aspects of a city. While it tells us about the general concept of a city, it does not tell us at what point in its growth a "town" can be considered a "city" or where a "city" begins and where it ends.
The problem is that there is no agreement on these matters. Different countries, municipalities and scientists use different definitions. For example, Shanghai, China, uses a vast area of 6,000 square kilometres to define itself. Nineteen million people live within those boundaries, but the area covers large patches of farmland as well as some villages. The city of London, Great Britain, on the other hand, has more than 7 million inhabitants. But the city boundaries used to define London do not include an extended "metropolitan region". If considered as a metropolitan region, London would have a population of 14 million. Other large cities have similar problems with ambiguous definitions.
In trying to define themselves, some cities use physical attributes: only an area that is "continuously built up". Others extend their definitions beyond this to include nearby settlements because the population and economy of those outlying areas are closely tied to the central city -- in this case, the definition is "economic". In yet another case, a larger area may be defined, which, as with Shanghai, would include some farmland and typically rural areas. Such a vast definition is often useful for planning and administrative purposes.
Cities have been called the highest forms of social organization. Think of the complexity of road systems, transportation, building laws, markets, food distribution, educational systems, etc., and you get an idea of what is meant by that statement. But that complexity didn't spring up over night. It is the result of long years of human development.
While the origin of cities dates back thousands of years, the city as we know it today dates back a few hundred years. Following industrialisation, large numbers of people moved to cities in search of jobs, mostly in factories, and since then there has been an unprecedented growth in the number and size of cities worldwide. This process is called "urbanization".
Urbanization is measured by the percentage change in a city's population from year to year. This is called the rate of "urban growth". For example, if your city had 200 people last year and has 210 people this year, its urban growth rate is 5%. On a global scale, the most rapid urban growth in history has taken place over the past 50 years. Whereas in 1950 fewer than 30% of people lived in a city, today 50% of humanity are urban dwellers.
Here is an interesting problem to consider: From 2000 to 2010 the proportion of the urban population living in slums has decreased from 39% to 32%. However, during the same period the number of slum dwellers has actually increased from, 776.7 million in 2000 to 827 million slum dwellers in 2010. How is it possible for the proportion to decrease while the numbers of slum dwellers is increasing?
Overcrowding in cities causes problems
with waste disposal, health and pollution. There are other
salient urban problems as well, among them violence, crime,
drugs, and the over-consumption of energy and other resources.
Most of these problems affect not only the city itself but the
countryside and often the entire world. In short, cities contain
within them the key challenges facing our civilisation.