In society, we can encounter some matters that we ought to do or have to do. We can classify these matters as three categories duty, responsibility, and obligation. People sometimes use these words interchangeably, but they refer to differences in the shade of meaning.
A word ‘Duty’ originates in one’s status, situation, occupation and our morality. Like duties as a parent, duties for country which is under the war, or duties as a doctor when a person is dying, a sense of duty comes from within us.