Economics is all about making rational economic decisions in a state of scarcity. Economics study how scarce economic resources are allocated.
And economics also analyzes the forces and trends that affect the economy as a whole, including the growth rate of output, the rate of the population that cannot find work, the rate at which price is increasing, and so on.
So, economics is the study of how people, societies, and nations make economic decisions, how they interact with each other, and how the collective system i.e., the economy as a whole works.
Considering these three major categories of working/functioning of economic science we can present the Ten Principles of Economics (Nicholas Gregory Mankiw). Understanding these principles helps us to find the answer to inquiries like what economics is all about, what central idea does economics has, and so on. Here are the powerpoints of a short explanation of all the Ten Principles of Economics.
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