What is the difference between Alien and Immigrant?

The tow terms "alien" and "immigrant" are used to refer to people who are not in their native place. However, immigrants are people that relocate; that is; they leave their country to another country, most likely in search of a better living. The medium of this immigration can be legal or illegal. Whichever way, the intention of an immigrant is just to stay away from his own homeland (probably the place of birth). Most immigrants migrate to another land in seek for protection or peace, in order to stay away from a particular disaster.

They also migrate to get a better job opportunity or better pay for better living. On the other hand, an alien (a legal one though) is one who lives in a foreign land on a temporary basis, probably for a short term purpose. For example, a student studying in another country is considered an alien. Aliens are mostly willing and looking up to going back to their homeland, while immigrants do not.