Indian people or Indians are citizens of India, the second most populous nation containing 17.50% of the world's population. "Indian" refers to nationality, not ethnicity or language. The Indian nationality consists of many regional ethno-linguistic groups, reflecting the rich and complex history of India. India hosts all major ethnic groups found in Indian Subcontinent. The diaspora populations with Indian ancestry, as a result of emigration, are somewhat widespread most notably in the UAE, Southeast Asia, United Kingdom, North America, Australia, South Africa and Southern Europe. Population estimates vary from a conservative 12 million to 20 million diaspora.