A currency pair refers to a specific combination of two currencies that are traded together in the foreign exchange market. It is represented by a symbol consisting of the ISO code for each currency, separated by a slash (e.g., USD/JPY represents the U.S. dollar and Japanese yen). The value of a currency pair is determined by the relative strengths or weaknesses of the two currencies involved, taking into account factors such as interest rates, inflation, and economic performance. Currency pairs are used to express prices in forex trading, with the base currency being the one being bought or sold, while the counter currency is the one being exchanged.