In the retail currency exchange market, a different buying rate and selling rate is quoted by money dealers. Most trades are to or from the local currency. The buying rate is the rate at which money dealers buy foreign currency, and the selling rate is the rate at which they sell the currency. People may need to exchange currencies in a number of situations.

An exchange rate is usually quoted in terms of the number of units of one currency that can be exchanged for one unit of another currency – e.g., in the form: I USD into 95.70 Pak rupees. In this example, the US$ is referred to as the “quote currency” (price currency, payment currency) and the Pak rupees is the “base currency” (unit currency, transaction currency)