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, but 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 the 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, New Zealand, South Africa, the Caribbean, and Southern Europe. Population estimates vary from a conservative 12 million to 20 million diaspora.