[[Image:Price of market balance.gif|thumb|right|Price of market balance:P - price Q - quantity of good S - supply D - demand P0 - price of market balance A - surplus of demand - when PB - surplus of supply - when P>P0]]Economics is the branch of social science that studies the production, distribution, and consumption of goods and services. The term economics comes from the Greek for oikos (house) and nomos (custom or law), hence "rules of the house(hold)."
A definition that captures much of modern economics is that of Lionel Robbins in a 1932 essay: "the science which studies human behaviour as a relationship between ends and scarce means which have alternative uses." Scarcity means that available resources are insufficient to satisfy all wants and needs. Absent scarcity and alternative uses of available resources, there is no economic problem. The subject thus defined involves the study of choice as they are affected by incentives and resources. Steven Pressman. Fifty Major...
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