The presidential system of government is a type of government in which most executive powers are vested in the President who is the chief executive (Head of State and Head of Government). The system was originally derived from the British monarchs of the 18th century who were very powerful.
In a presidential system of government, the President is both the ceremonial and executive head of state. That is, the president combines the offices of Head of State and Head of Government at the same time. In this regard, the President performs a number of functions. In particular, he enforces all laws, serves as the Commander in Chief of the Armed Forces, appoints important political office holders and grants pardon and mercy to offenders.