Federal Government: Power is divided between a central authority and constituent units (states/provinces). Both levels enjoy independent powers guaranteed by the constitution. Neither can override the other. Example: India, USA.
Unitary Government: Either there is only one level of government, or the sub-units are subordinate to the central government. The central government can pass orders to provincial governments. Example: Sri Lanka.
Key Difference: In a federal system, the central government cannot order the state government; both are separately answerable to the people. In a unitary system, the central government holds supreme authority.
Source: Chapter 2, 'What is Federalism?'
---