What is the main difference between …

Federalism is a system of government in which the power is divided between a central authority and various constituent units of the country. Federal governments have two or more tiers of government. In a federal form of government, the central government shares its powers with the various constituent units of the country. Both types of governments enjoy independent powers and are separately answerable to the people. For example, in India, power is divided between the Central Government and the various State governments. In a unitary form of government, either there is one level of government or the sub-units are subordinate to the Central government. In this, the Central government can pass orders to the provincial or the regional government. For example, in Sri Lanka, the national government has all the powers.