Which type of migration specifically occurs between countries?

International migration refers to the movement of people from one country to another. This type of migration can occur for a variety of reasons, including economic opportunities, educational pursuits, conflict, or family reunification. By definition, international migration involves crossing national borders, which distinguishes it from other types of migration that occur within a single country.

Internal migration, on the other hand, pertains to movements within a country, such as relocating from one state to another, and does not involve crossing international borders. Voluntary migration generally describes the choice of individuals to move for reasons that improve their well-being, while it could occur either internationally or internally. Rural-urban migration specifically focuses on the movement from rural areas to urban centers, which is also an example of internal migration.

Therefore, the proper classification of migration that occurs between countries is international migration, as it specifically involves crossing borders and moving from one sovereign nation to another.