A federation consists of two parts of administrative machinery, viz. The central and provincial (regional). The provincial or regional parts are known as the units of a federation. These units are often called as “State” by courtesy.
India is a federation consisting of 25 States. However, here the term “State” is loosely used. The units of the India federation have-population, territory and government but they have no sovereign power. They cannot declare war or conclude treaties with foreign States. They enjoy only a limited power. Hence, Bihar, Orissa, Gujarat, West Bengal, etc. are not States in true sense of the term.