Bifurcation of power between Union and States :
Article 1(1) of Constitution of India states that India, that is Bharat, shall be a Union of States.
Thus, India has federal structure of governance, like USA, Australia, UAE etc. i.e. Union Government and State Governments.
Naturally, when there are two authorities, bifurcation of power is required between Union and State to avoid conflicts, disputes and ambiguities.
Article 245(1) of Constitution of India states that subject to provisions of Constitution, Parliament may make laws for whole or any part of India and Legislature of a State may make laws for the whole or part of the State.
Article 245(2) of Constitution of India clarifies that law made by Parliament can have extra-territorial operation.
Article 246(1) of the Constitution specifies that Parliament has exclusive powers to make laws with respect to any of the matters enumerated in List I in the Seventh Schedule to Constitution.
As per Article 246(3) of Constitution of India, State Governments have exclusive powers to make laws with respect to matters enumerated in List II (State List).
In respect of matters enumerated in List III (termed as ‘Concurrent List’), both Parliament and State Governments have power to make laws.
As per Article 246(4) of Constitution of India, Parliament can make laws in respect of Union Territories even in respect of matters covered in State List.