Appreciation of currency means increase in the value of one country’s currency in comparison to other country’s currency due to market forces (demand & supply).
Example:-
In floating/Flexible Exchange Rate Regime:- 1$ = 70, if $ rate decreases from 70 to 60. Here, value of India’s currency will be increased or price of foreign exchange will be decreased.
Revaluation of Currency :- means increase in the value of one country’s currency in comparison to other country’s currency due to Government intervention or by monetary authority (Central bank).
In fixed/Pegged Exchange Rate Regime :- 1$ = 70, if $ rate decreases from 70 to 60. Here, the value of India’s currency will be increased or price of foreign exchange will be decreased.
Import becomes cheap.