A conversion operation object based on the change of one currency rate against another. The example of the currency pair is USD/JPY. Currency pairings are done because it is the rate of exchange of one currency to another currency that is measured in the FOREX market. A currency cannot be traded against itself, and that is why currencies are paired so that they reflect the rate of exchange of one currency against another. In a currency pair, the first listed currency is the base currency while the currency listed on the right is known as the counter currency.