Tribes have been classified in India according to their “permanent” and “acquired” traits.
Permanent traits have region, language, physical characteristics and ecological habitat. The ecological habitats covered include hills, rural plains, forests and urban industrial regions.
In terms of language, tribes are categorised into four categories. Two of them are Indo Aryan and Dravidian and the other two are Austric and Tibeto-Burman.
In physical-racial terms, tribes are classified under the Negrito, Australoid, Mongoloid, Dravidian and Aryan categories.
In terms of size, tribes vary a lot. The biggest tribes are the Gonds, Bhils, Santhals, Oraons, Minas, Bodos and Mundas.
Acquired Traits: The following two main criteria are used in the category of acquired traits:
Mode of livelihood: Under this category, tribes can be categorised into fishermen, food gatherers and hunters, shifting cultivators, peasants and plantation and industrial workers.
Extent of incorporation into Hindu society: The dominant classification both in academic sociology as well as in politics and public affairs is the degree of assimilation into Hindu society.