The document discusses the categorization and naming of castes and social groups in colonial India and Tamil Nadu. It describes how the British colonial government categorized Indians according to family, religion, caste and village in censuses starting in 1871. In 1916 and 1917, certain social groups including aboriginal tribes, untouchables and criminal tribes were officially defined and listed as "depressed classes". This and other terms like "Panchama" were criticized by Tamil intellectuals as attempts to humiliate and oppress people. Alternative terms like "Adi-Tamilar", "Sathipedamatra Dravidan", and "Adi-Dravida" were proposed and eventually became commonly used references for Dalits