National currency is the official money used by a country for transactions and trade. It is issued and regulated by the country's central bank, which ensures its stability and value. Each nation typically has its own unique currency, such as the US Dollar, Euro, or Japanese Yen, which is used for everyday purchases and economic activities. The value of national currency can fluctuate based on various factors, including inflation, interest rates, and economic performance. Exchange rates determine how much one currency is worth in relation to another, affecting international trade and travel. A stable national currency is essential for a healthy economy.