Migration is the movement of people from one place to another. It can happen within a country or across national borders. Migration may be temporary or permanent.

People move for many reasons, such as work, safety, education, or joining family members. Early humans migrated out of Africa more than 60,000 years ago, and movement has continued throughout history. Today, large cities often grow as people move from rural areas.

Migration is measured using population data and official records. It is studied by governments and researchers to understand how populations change over time.