The distribution of population in the world is uneven. Some areas are very crowded while some are sparsely populated. There are various reasons behind uneven distribution:
Geographical factors: Favorable topography, availability of mineral and freshwater resources, favorable climate and soil fertility are some of the reasons affecting population distribution. Indo-Gangetic Plains, Diamond Mines of South Africa, etc, are densely populated.
Social and cultural factors: Areas of better housing, education and health facilities are more populated. Places of religious and cultural significance also attract people e.g., Varanasi, Jerusalem, etc.
Economic factors: Places having more industries, transportation and communication facilities provide better employment opportunities. People are attracted to these places because of these reasons, e.g., Mumbai, Osaka etc.