Wikipedia refers to marginal value as, the change in economic value associated with a unit change in output, consumption, or some other economic choice variable. Marginal value can also be defined as the additional value added from the next consumed unit. For example, giving a slice of bread to someone without any would be of great value to them. However, the next slice would not have as much value.
A citizen is a participatory member of a political community. Citizenship is gained by meeting the legal requirements of a national, state, or local government. A nation grants certain rights and privileges to its citizens.
A digital citizen refers to a person utilizing information technology (IT) in order to engage in society, politics, and government participation. K. Mossberger, et al. define digital citizens as those who use the Internet regularly and effectively.