Money Supply is the stock of currency and liquid instruments available in the economy. It generally includes cash, coins and balances held in checking and savings accounts.
Measures of Money Supply
Four alternative measures of money supply (adopted by RBI since 1977)
Here C = Currency held by public
DD = Net demand deposits of banks
OD = Other deposits of the RBI
AMR = Aggregate Monetary Resources.
In the above definitions, M1 is called narrow money and M3 is called broad money. Currency includes paper currency and coins only. Other deposits of the RBI includes deposits other than those held by the Govt (Central and State govt.), banks and a few others. They include demand deposits of quasi-government institutions (like the IDBI), foreign central banks and governments, the IMF and the World Bank etc.