Define: migration
The movement of people from one permanent home to another for at least one year (UN).
Define: emigration
People moving out of a country as part of an international migration.
Define: immigration
People moving into a country as part of international migration.
Define: international migration
The movement of people across international borders.
Define: internal migration
When people move from one place to another within a country.
Define: net migration
The balance between people moving into a region and the people moving out.
Define: distance decay
The idea that the number of migrants declines as the distance between the source area and destination increases.
Define: migrant stream
Migrants sharing a common source area and destination.
Define: step migration
When a move is done in stages.
Causes of migration: push factors
Causes of migration: pull factors.
Examples of constraints, obstacles and barriers.