There are three major components of population growth which are as follows:

(i) Birth rate is a major component of population growth because in India, birth rate has always been higher than death rate, and it is the number of live births per thousand persons in a year.

(ii) The second main cause of the rate of growth of the Indian population has been the rapid decline in death rates; it is the number of deaths per thousand persons in a year. Till 1980, high birth rates and declining death rates led to a large difference between birth rates and death rates resulting in higher rates of population growth.

(iii) The third major component of population growth is migration, which is movement of people across regions and territories; there can be two types of migration internal and international. Internal migration does not change the size of population, but influences the distribution of population within the nation; it plays a vital role in changing the composition and distribution of population.