ABSTRACT
It is no doubt that the rampant urbanization is one of the most significant and complex socioeconomic phenomena that the world has experienced since the beginning of the twentieth century (Lu, 2011). If current trends hold, by 2050 the number of people living in cities will nearly double, from 3.6 billion in 2011 to more than 6 billion (Macomber, 2013). The Population Reference Bureau has predicted the trends in urbanization by regions, as depicted in Figure 12.1 .
