The rate at which one currency will be exchanged for another is known as the exchange rate in the world of finance. Most often, currencies are national ones, but they can also be supra-national ones like the euro or sub-national ones like Hong Kong.
The value of one country's currency in respect to another currency is also thought of as the exchange rate.
 An interbank exchange rate of 114 Japanese yen to the US dollar, for instance, indicates that 114 will be converted into $1 or that $1 will be converted into 114. In this instance, it is said that the cost of a dollar in terms of yen is 114, or, translated into dollars, that the cost of a yen in terms of yen is $1/114.
Each nation chooses the regime of exchange rates that will be used for its respective currency. A currency might be hybrid, pegged (fixed), or floating, for instance. Governments have the authority to set restrictions and limits on currency rates. A nation's currency may be strong or weak. On the ideal national exchange rate, the economic literature is divided (unlike on the subject of trade where free trade is considered optimal). National exchange rate regimes, on the other hand, reflect political factors. 
Exchange rates are set under floating exchange rate regimes on the foreign exchange market, which is continuously active and available to a wide variety of buyers and sellers: except on weekends, which begin with trade at 20:15 GMT on Sunday.
until Friday at 22:00 GMT). In contrast to the forward exchange rate, which is stated and exchanged today but is intended for delivery and payment on a certain future date, the spot exchange rate is the rate in effect at the time.
Money dealers will provide various purchasing and selling prices in the retail foreign exchange market. Most transactions are made in or out of local currency. The buying rate and selling rate are the rates at which currency traders will purchase and sell foreign currency, respectively. The dealer's margin (or profit) from trading will be factored into the quoted rates, or else the margin may be recovered by a commission or another method.