The census of India collects and tabulates information on rural and urban areas separately and is therefore the most important source of data for the study of urbanisation in India.
Till 1961, the definition of an “urban” unit was somewhat confusing. According to this definition, all municipalities were considered urban. Secondly, the definition covered all the civil lines and cantonments not included in the municipal limits.
All places with 5,000 or more inhabitants, which the Provincial Census Superintendent considered to be urban, were also included on the basis of their character, density of population and their economic and historic importance.
Any place, which had less than 5,000 inhabitants, was also considered as urban if the Census Superintendent believed it to be so. Thus, the distribution between rural and urban localities did not depend entirely on the size of the population but on the discretion of the census authorities.
Since the 1961 census, more rigorous criteria have been adopted for classifying localities as urban. In the 1961 Census of: India the definition of urban area adopted is as follows:
(a) All places with a municipality, corporation, cantonment board or notified town area committee, etc.
(b) All other places which satisfy the following criteria: (i) a minimum population of 5,000;
(ii) At least 75 per cent of male working population engaged in non-agricultural pursuits; and
(iii) A density of population of at least 400 persons per square kilometer.
Bose has pointed out that in 1961, only 59.6 per cent of the towns fulfilled all the first three criteria, while only 43.1 per cent of the towns satisfied all the four conditions. As pointed out earlier in this Chapter, towns are classified into six groups according to population size.