What is 'relative deprivation' in Sociology?

This refers to a theory of social change that attributes drastic events like social and political revolutions to the desire among a group of people within society to acquire the privileges that are enjoyed by other privileged groups. In other words, social change is seen as the result of the feeling of deprivation or other forms of serious discontent experienced by a group of people. Relative deprivation could be caused by economic or other social inequalities among various social groups. It is believed that group members who were earlier dispersed may find common ground in a cause that leads them to ignore their individual interests and unite under a single cause.

Source: The Hindu, 21/12/2018