The supremacy of the constitution means that both, the Union and the State Governments, shall operate within the limits set by the Constitution.And both the union government and the central government derive their powers from the constitution.: The constitution of India is a rigid constitution and this is one of the basic features of federal constitution.The question whether the Indian Constitution could be called a federal constitution troubled the minds of the members of the Constituent Assembly.
In this system the central government and the governments of the units act within a well defined sphere, co-ordinate and at the same time act independently. Wheare defines federal government as an association of states, which has been formed for certain common purposes, but in which the member states retain a large measure of their original independence.As such amendments can only be made by the Union Parliament.All India Services such as IAS and IPS have been created which are kept under the control of the Union.A unitary system is governed constitutionally as one single unit, with one constitutionally created legislature. A unitary state is a sovereign state governed as one single unit in which the central government is supreme and any administrative divisions (sub national units) exercise only powers that the central government chooses to delegate.This is one of the federal features of the Indian constitution.