Urbanisation and Urbanism are the two most widespread phenomena of the twentieth century. Urbanisation is the Absolute growth of cities, both in numbers and size, as masses of people move into the urban centers of the world. Every nation on earth is undergoing urbanization. Cities today are magnets both for the indigenous rural populations and for foreign immigrants, many of whom are political refugees. Urbanism, the adoption of urban lifestyles and values, is a product of urbanisation, but is not necessarily related to living in a large city. The global urban pattern is changing through urbanisation and the spread of urbanism.