Appreciation of Currency
Appreciation of a currency refers to an increase in the value of a country's currency relative to other currencies in the foreign exchange market. This can happen due to various factors such as strong economic performance, high interest rates, political stability, or increased demand for the currency.
- Causes of Appreciation: Factors like increased foreign investment, higher export earnings, or a decrease in inflation rates can lead to the appreciation of a currency.
- Effects of Appreciation: A stronger currency can make imports cheaper, lower inflation rates, and reduce the cost of foreign debt. However, it can also harm export competitiveness and lead to a trade deficit.

Revaluation of Currency
Revaluation of a currency is a deliberate action taken by a country's central bank or government to increase the value of the currency in the foreign exchange market. This is typically done by adjusting the exchange rate of the currency against other currencies.
- Purpose of Revaluation: Revaluation is usually done to address trade imbalances, control inflation, or boost the purchasing power of the currency.
- Effects of Revaluation: Revaluation can help reduce the trade deficit, attract foreign investment, and stabilize the economy. However, it can also make exports more expensive and harm export-oriented industries.

Key Differences
- Appreciation is Market-Driven: Appreciation occurs naturally in response to market forces, while revaluation is a deliberate policy decision.
- Timing and Control: Appreciation can happen quickly and uncontrollably, while revaluation is a planned and controlled action.
- Impact on Economy: Appreciation can have both positive and negative effects on the economy, while revaluation is usually aimed at achieving specific economic goals.