Both the terms immigration ("moving into a population") and emigration ("moving out of a population") come from the Latin word migrare ("to move"). What do you think the prefixes im- and e- mean?

im means into

e means out of

Explanation:

Using the definitions of immigration and emigration as points of reference, the following explanation applies.

Both terms are derived from migration which means moving from one place to another.

By further explanation:

The "im" in the definition of immigration means "into" while the "e" in the definition of emigration means "out of"