54% of the world's population now lives in urban areas and it is expected to increase to 66% by 2050 as per UN report "World Urbanization Prospects 2014". The report further highlights the emergence of 28 megacities, i.e. urban areas with 10 million inhabitants, around the world, compared to 10 megacities in 1990. Currently, Tokyo (Japan) is the world's most crowded city with 38 million inhabitants, followed by New Delhi (India) (25 million), Shanghai (China) (23 million) and Mumbai (India) (21 million).
