The supply of money consists of various components. M1 and M4 are also components of the money supply.
M1 = Currency notes and coins with the public (C) + Demand deposits with the banks (DD) + Other deposits with the RBI (OD)
Thus. M1 = C + DD + OD
and M4 = M1 + Saving deposit with post office saving bank (SD) + Total deposits with post office savings organisation (TDP)
Thus, M4 = M2 + TDP
where M2 = M1 + SD.
