What Is An Immortal Soul?

The term immortal soul can be used to describe a person who can be remembered for his deeds even when the person dies.
      
If you are taking the meaning of the word literally then you can say that it is a kind of soul that never dies but we all know that every one who has come to this planet has to die one day. But it is believed that a person if doing very good deeds when he is in this world, he attains immortality and every one remembers him even when the person has left the material world for the heavenly world.  
     
Some of the examples that you can cite as an example of immortal soul include Mother Teresa and also Princess Diana.