Migration is a form of geographical mobility or spatial mobility between geographical unit and another, generally involving a change in residence from the place of origin or place of departure to the place of destination or place of arrival. Such migration is called permanent migration and should be distinguished from other forms of movements, which do not involve a permanent change of residence. Migration is a very selective process. Migration is not for a pleasure. Migration is not merely the physical movements of individuals and groups involve a lot of strain in their social, economic, cultural and other aspect of life. It is a subject of keen interest not only to the demographers but also to sociologist, anthropologist, economist and political scientist movements of people, specially rural people from the land to the cities, from one country to another and from one continent to another is an international phenomenon and not a phenomenon of modern times. It concerns not only developing countries but also those which are highly industrialized and affects not only the more or capitalized countries but also the socialist change of the move or open the voluntary and involuntary nature of the act and destination. Is made between external and internal migration.
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