Distinguish between the Unitary and Federal systems of government.
Under the unitary system, either there is only one level of government or the sub-units are subordinate to the central government. The central government can pass on orders to the provincial or the local government.
In federal system government and its powers are divided at Union and State level, in some countries even at local self-level. In this system, the central government cannot order the state government to do something.
In federal system State government has powers of its own for which it is not answerable to the central government. Both these governments are separately answerable to the people.