It has, after China, the largest population of any country in the world.
Most people living in India are subject to the caste system.
The caste system in India is part of the Hindu religion, to which 82 per cent of the people belong. The caste system used to regulate who did what jobs, how rich people were likely to become, and many aspects of their lives. Only very high caste Hindus, called Brahmins, could become Hindu priests. Lower-caste people were generally the poorest. The lowest Hindu castes were called untouchables and did the jobs no-one else wanted to.