The word "economics" is derived from a Greek word "oikonomia" which means "household management" or "management of house affairs" i.e., how people earn income and resources and how they spend them on their necessities, comforts and luxuries. With the passage of time, the word "oikonomia" was used for an economy as whole in the sense that how a nation takes steps to fulfill its desires and preferences with the help of scarce means. That's why economics was called political economy in its early ages.