Ethnic and religious composition; urbanisation

Urbanisation is the growth in the number and share of towns and city dwellers and the spread of the urban way of life. Its level is measured by the share of the urban population in the total, as a percentage. In 1800 only about 3 % of humanity lived in cities; today more than half (about 57–58 %) do. By urban share, countries are highly urbanised (over 75 %: USA, Japan, Belgium), medium (50–75 %: South Africa, China, Indonesia) or low (under 50 %: Bangladesh, Egypt and others); in Uzbekistan the figure is around half. The highest levels are in North and Latin America, the lowest in Africa and Asia, but urbanisation is growing fastest there. In developing countries pseudo-urbanisation sometimes occurs: newcomers from villages build unplanned districts at the edge of big cities without infrastructure such as water, sewers and roads. When cities grow and merge, an agglomeration (a group of cities) forms, and when agglomerations merge, a megalopolis appears (for example Boswash in the north-east USA and Tokaido in Japan).