Answer:
'Immigration' is the process of 'moving or passing into a foreign country to stay permanently.' While 'emigration' denotes 'leaving a particular region or native country to reside in another.' Thus, the key difference between the two terms is that the former(immigrate) stands for living in an alien/new country while the latter(emigrate) means leaving a location to stay in the other.
For example; if a person is relocating into a country with the purpose of residing there permanently exemplifies 'immigration.' And if a person while living in his native country applies for permanent residence in the other country and leaves the former for the latter, it is an example of emigration.