Internal migration or domestic migration is human migration within a country. Internal migration tends to be travel for education and for economic improvement or because of a natural disaster or civil disturbance,[1] though a study based on the full formal economy of the United States found that the median post-move rise in income was only 1%.[2]
Cross-border migration often occurs for political or economic reasons. A general trend of movement from rural to urban areas, in a process described as urbanisation, has also produced a form of internal migration.[3]