The Foreign Exchange Market, commonly referred to as FOREX, is a worldwide market for buying and selling currencies. The Forex market handles a huge volume of transactions 24 hours a day, 5 days a week. Daily exchanges are estimated to be worth approximately $1.5 trillion (US dollars).

Currency exchange, the exchanging of one currency for another is a needed in frequent instances. Most people will encounter currency exchange when traveling to a country that deals in a different currency then their own. They are able to exchange currency at their bank, currency exchange bureau , even the airport. The financial institution will convert their domestic currency into the foreign currency needed. The average consumer may also come into contact with currency exchange when making a purchase online from a foreign retailer. When reviewing their credit card statement they will notice the funds deducted from their account were in their currency rather than the foreign currency price listed on the website.

Even though these currency exchanges may be reasonably small transactions, the collection of all such transactions is substantial. Businesses are required to convert currencies when completing financial transactions outside of their home country. When a business exports goods to another country and receives payment that payment is typically in the foreign currency and must be converted into their currency for the transaction to be complete and vice versa when they are making purchases overseas.

Big firms and large companies exchange huge amounts of currency each year. The balance sheet can be affected depending on the timing of when they convert the currency. Investors and entrepreneurs need to exchange currency whenever they trade in any overseas investment, such as bonds, equities, bank deposits, or real estate.

Speculators and investors also trade currencies directly in order to take advantage of the  movements in the currency exchange markets. Investment banks and Commercial banks transact currencies as one of their services for banking, deposit and lending customers. These establishments also mostly involve in the currency market for hedging and exclusive trading purposes.

In general, a currency exchange rate is given as a pair,comprising of a bid price and an ask price. When purchasing a currency pair you are dealing with the ask price. The ask price represents what has to be paid in the quote currency to obtain one unit of the base currency. When selling you are dealing with the bid price and this represents what will be obtained in the quote currency when selling one unit of the base currency. When buying, the currency pair implies buying the first, base currency and selling (short) an equivalent amount of the second, quote currency (to pay for the base currency). A trader does not need  to own the quote currency prior to selling, as it is sold short.