Economics is concerned with the study of economic problems at the level of an economy as a whole, on one side and on the other, it is concerned with the study of an individual too.
The subject matter of economics is studied under two broad branches viz microeconomics and macroeconomics.
Vital theories or studies of microeconomics are:
(i) Theory of consumer behaviour,
(ii) Theory of price.
(iii) Theory of producer behaviour.
Vital theories or studies of
(i)Theory related to equilibrium level of output and employment.
(ii)Theory related to inflationary and deflationary gap in the economy.
(iii)Theory of multiplier.
(iv)Study of government budget.
(v)Study of exchange rate and Balance of Payments (BoP).