2. The balance between the size of the population and natural resources (i.e., land, water, forest, minerals, etc.) of a country is significant. Any change in this balance brings social change. Industrialised nations require to maintain this balance. Otherwise, they will not be in a position to keep the continuity of growth and development due to shortage of resources.

(ii) Social Change means changes in social structure and social relationships of a society. Under social change the changes in family marriage, kinship, economy, politics, age, distribution, birth and death rates of population, etc. are included.

(iii) Cultural Change means changes in the culture of a society, i.e., ideas, knowledge, values, morality, religion, art, etc.

(iv) Environment : Ecology, commonly known as environment.

(b) Technology : Knowledge of tools and techniques by which man produces something for their use in society.

(c) Evolution : It means gradual (or slow) process of growth and development of society towards more developed stage.

(d) Revolution : Through conflict between groups sudden and overall change in the basic form of the society takes place. This process is revolution.