Emigration is the act of leaving a resident country or place of residence with the intent to settle elsewhere (to permanently leave a country). Conversely, 'immigration' describes the movement of people into one country from another (to permanently move to a country). Hence one might 'emigrate from' one's native country to 'immigrate to' another country. Both are acts of migration across national or other geographical boundaries.

Patterns of emigration have been shaped by numerous economic, social, and political changes throughout the world in the last few hundred years. For instance, millions of individuals fled poverty, violence, and political turmoil in Europe to settle in the Americas and Oceania during the 18th, 19th, and 20th centuries. Likewise, millions left South China in the Chinese diaspora during the 19th and early 20th centuries.

The rate of emigration has continued to grow, reaching 280 million in 2017. Some countries restrict the ability of their citizens to emigrate to other countries. North Korea maintains one of the strictest emigration bans in the world. Other countries with tight emigration restrictions at one time or another included Angola, Egypt, Ethiopia, Mozambique, Somalia, Afghanistan, Burma, Cambodia, Laos, North Vietnam, Iraq, South Yemen and Cuba.

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