The Prime Minister of India is the head of the executive branch of the Government of India. His position is distinct from that of the President of India, who is the head of the State.
As India follows a parliamentary system of government modelled after the Westminster system, most of the executive powers are exercised by the Prime Minister. He acts as an advisor to the President and is the leader of the Council of Ministers.
The President appoints the Prime Minister of India and on his advice, appoints the Council of Ministers. The Prime Minister can be a member of either the Lok Sabha or the Rajya Sabha.