The World Population Day is celebrated annually on July 11. The genesis of this date goes back to 11 July 1987 when the world's population crossed 5 billion people.
The process of counting the number of people in a country is known as Census. In India census is taken once in 10 years.
The UNFPA (United Nations Population Fund) is the central UN organization that works in this area.
India accounts for 2.4 per cent of the world surface area and 16.7 per cent of the world population. India is thus the second most populous country in the world.
Sex ratio, refers to the number of females per thousand males. It is 933 for India according to the 2001 census i.e. there are 933 women for every 1000 women in the country.
Population density refers to the number of persons living per sq.km. The population density of England is much higher than that of India. Yet, one does not consider England to be an overpopulated country.