The foreign exchange market is the "place" where currencies are traded. Currencies are important to most people around the world, whether they realize it or not, because currencies need to be exchanged in order to conduct foreign trade and business. If you are living in the U.S. and want to buy cheese from France, either you or the company that you buy the cheese from has to pay the French for the cheese in euros (EUR). This means that the U.S. importer would have to exchange the equivalent value of U.S. dollars (USD) into euros. The same goes for traveling. A French tourist in Egypt can't pay in euros to see the pyramids because it's not the locally accepted currency. As such, the tourist has to exchange the euros for the local currency, in this case the Egyptian pound, at the current exchange rate.

One unique aspect of this international market is that there is no central marketplace for foreign exchange. Rather, currency trading is conducted electronically over-the-counter (OTC), which means that all transactions occur via computer networks between traders around the world, rather than on one centralized exchange. The market is open 24 hours a day, five and a half days a week, and currencies are traded worldwide in the major financial centers of London, New York, Tokyo, Zurich, Frankfurt, Hong Kong, Singapore, Paris and Sydney - across almost every time zone. This means that when the trading day in the U.S. ends, the forex market begins anew in Tokyo and Hong Kong. As such, the forex market can be extremely active any time of the day, with price quotes changing constantly.

After the accord at Bretton Woods in 1971, more major currencies were allowed to float freely against one another. The values of individual currencies vary, which has given rise to the need for foreign exchange services and trading.

Commercial and investment banks conduct most of the trading in the forex markets on behalf of their clients, but there are also speculative opportunities for trading one currency against another for professional and individual investors.

There are actually three ways that institutions, corporations and individuals trade forex: the spot market, the forwards market and the futures market. The forex trading in the spot market always has been the largest market because it is the "underlying" real asset that the forwards and futures markets are based on. In the past, the futures market was the most popular venue for traders because it was available to individual investors for a longer period of time. However, with the advent of electronic trading and numerous forex brokers, the spot market has witnessed a huge surge in activity and now surpasses the futures market as the preferred trading market for individual investors and speculators. When people refer to the forex market, they usually are referring to the spot market. The forwards and futures markets tend to be more popular with companies that need to hedge their foreign exchange risks out to a specific date in the future.

More specifically, the spot market is where currencies are bought and sold according to the current price. That price, determined by supply and demand, is a reflection of many things, including current interest rates, economic performance, sentiment towards ongoing political situations (both locally and internationally), as well as the perception of the future performance of one currency against another. When a deal is finalized, this is known as a "spot deal". It is a bilateral transaction by which one party delivers an agreed-upon currency amount to the counter party and receives a specified amount of another currency at the agreed-upon exchange rate value. After a position is closed, the settlement is in cash. Although the spot market is commonly known as one that deals with transactions in the present (rather than the future), these trades actually take two days for settlement.

Unlike the spot market, the forwards and futures markets do not trade actual currencies. Instead they deal in contracts that represent claims to a certain currency type, a specific price per unit and a future date for settlement.

In the forwards market, contracts are bought and sold OTC between two parties, who determine the terms of the agreement between themselves.

In the futures market, futures contracts are bought and sold based upon a standard size and settlement date on public commodities markets, such as the Chicago Mercantile Exchange. In the U.S., the National Futures Association regulates the futures market. Futures contracts have specific details, including the number of units being traded, delivery and settlement dates, and minimum price increments that cannot be customized. The exchange acts as a counterpart to the trader, providing clearance and settlement.

Both types of contracts are binding and are typically settled for cash for the exchange in question upon expiry, although contracts can also be bought and sold before they expire. The forwards and futures markets can offer protection against risk when trading currencies. Usually, big international corporations use these markets in order to hedge against future exchange rate fluctuations, but speculators take part in these markets as well.

Note that you'll see the terms: FX, forex, foreign-exchange market and currency market. These terms are synonymous and all refer to the forex market.

Companies doing business in foreign countries are at risk due to fluctuations in currency values when they buy or sell goods and services outside of their domestic market. Foreign exchange markets provide a way to hedge currency risk by fixing a rate at which the transaction will be completed.

To accomplish this, a trader can buy or sell currencies in the forward or swap markets in advance, which locks in an exchange rate. For example, imagine that a company plans to sell U.S.-made blenders in Europe when the exchange rate between the euro and the dollar (EUR/USD) is €1 to $1 at parity.

The blender costs $100 to manufacture, and the U.S. firm plans to sell it for €150 – which is competitive with other blenders that were made in Europe. If this plan is successful, the company will make $50 in profit because the EUR/USD exchange rate is even. Unfortunately, the USD begins to rise in value versus the euro until the EUR/USD exchange rate is .80, which means it now costs $0.80 to buy €1.00.

The problem the company faces is that it, while it still costs $100 to make the blender, the company can only sell the product at the competitive price of €150, which when translated back into dollars is only $120 (€150 X .80 = $120). A stronger dollar resulted in a much smaller profit than expected.

The blender company could have reduced this risk by shorting the euro and buying the USD when they were at parity. That way, if the dollar rose in value, the profits from the trade would offset the reduced profit from the sale of blenders. If the USD fell in value, the more favorable exchange rate will increase the profit from the sale of blenders, which offsets the losses in the trade.

Hedging of this kind can be done in the currency futures market. The advantage for the trader is that futures contracts are standardized and cleared by a central authority. However, currency futures may be less liquid than the forward markets, which are decentralized and exist within the interbank system throughout the world.

Factors like interest rates, trade flows, tourism, economic strength and geopolitical risk affect supply and demand for currencies, which creates daily volatility in the forex markets. An opportunity exists to profit from changes that may increase or reduce one currency's value compared to another. A forecast that one currency will weaken is essentially the same as assuming that the other currency in the pair will strengthen because currencies are traded as pairs.

Imagine a trader who expects interest rates to rise in the U.S. compared to Australia while the exchange rate between the two currencies (AUD/USD) is .71 (it takes $.71 USD to buy $1.00 AUD). The trader believes higher interest rates in the U.S. will increase demand for USD, and therefore the AUD/USD exchange rate will fall because it will require fewer, stronger USD to buy an AUD.

Assume that the trader is correct and interest rates rise, which decreases the AUD/USD exchange rate to .50. This means that it requires $.50 USD to buy $1.00 AUD. If the investor had shorted the AUD and went long the USD, he or she would have profited from the change in value.

There are two distinct features to currencies as an asset class:

An investor can profit from the difference between two interest rates in two different economies by buying the currency with the higher interest rate and shorting the currency with the lower interest rate. Prior to the 2008 financial crisis, it was very common to short the Japanese yen (JPY) and buy British pounds (GBP) because the interest rate differential was very large. This strategy is sometimes referred to as a "carry trade."

Currency trading was very difficult for individual investors prior to the internet. Most currency traders were large multinational corporations, hedge funds or high-net-worth individuals because forex trading required a lot of capital. With help from the internet, a retail market aimed at individual traders has emerged, providing easy access to the foreign exchange markets, either through the banks themselves or brokers making a secondary market. Most online brokers or dealers offer very high leverage to individual traders who can control a large trade with a small account balance.

Trading currencies can be risky and complex. The interbank market has varying degrees of regulation, and forex instruments are not standardized. In some parts of the world, forex trading is almost completely unregulated.

The interbank market is made up of banks trading with each other around the world. The banks themselves have to determine and accept sovereign risk and credit risk, and they have established internal processes to keep themselves as safe as possible. Regulations like this are industry imposed for the protection of each participating bank.

Since the market is made by each of the participating banks providing offers and bids for a particular currency, the market pricing mechanism is based on supply and demand. Because there are such large trade flows within the system, it is difficult for rogue traders to influence the price of a currency. This system helps create transparency in the market for investors with access to interbank dealing.

Most small retail traders trade with relatively small and semi-unregulated forex brokers/dealers, which can (and sometimes do) re-quote prices and even trade against their own customers. Depending on where the dealer exists, there may be some government and industry regulation, but those safeguards are inconsistent around the globe. 

Most retail investors should spend time investigating a forex dealer to find out whether it is regulated in the U.S. or the U.K. (dealers in the U.S. and U.K. have more oversight) or in a country with lax rules and oversight. It is also a good idea to find out what kind of account protections are available in case of a market crisis, or if a dealer becomes insolvent.

Pro: The forex markets are the largest in terms of daily trading volume in the world and therefore offer the most liquidity. This makes it easy to enter and exit a position in any of the major currencies within a fraction of a second for a small spread in most market conditions.

Challenge: Banks, brokers and dealers in the forex markets allow a high amount of leverage, which means that traders can control large positions with relatively little money of their own. Leverage in the range of 100:1 is a high ratio but not uncommon in forex. A trader must understand the use of leverage and the risks that leverage introduces in an account. Extreme amounts of leverage have led to many dealers becoming insolvent unexpectedly.

Pro: The forex market is traded 24 hours a day, five days a week—starting each day in Australia and ending in New York. The major centers are Sydney, Hong Kong, Singapore, Tokyo, Frankfurt, Paris, London and New York.

Challenge: Trading currencies productively requires an understanding of economic fundamentals and indicators. A currency trader needs to have a big-picture understanding of the economies of the various countries and their inter-connectedness to grasp the fundamentals that drive currency values.

[Note: One of the underlying tenets of technical analysis is that historical price action predicts future price action. Since the forex market is a 24-hour market, there tends to be a large amount of data that can be used to gauge future price movements. This makes it the perfect market for traders that use technical tools. If you want to learn more about technical analysis from one of the world's most widely followed technical analysts, check out the Technical Analysis course on the Investopedia Academy.]

For traders—especially those with limited funds—day trading or swing trading in small amounts is easier in the forex market than other markets. For those with longer-term horizons and larger funds, long-term fundamentals-based trading or a carry trade can be profitable. A focus on understanding the macroeconomic fundamentals driving currency values and experience with technical analysis will help new forex traders to become more profitable