Pardoning powers of the President comes under Article 72 of the constitution.
Pardon: To free the criminal from all Punishments.
Commutation: To substitute one form of punishment with another without changing the sentence i.e reduction of a judicial sentence, especially a sentence of death to the another less severe punishment.
Respite: Change the nature of punishment due to some special condition i.e awarding lesser punishment due to the pregnancy of women offenders.
Reprieve: Temporarily deferred punishment.
Remission: Reducing the period of a sentence without changing its character.