Unlike a stock market, the foreign exchange market is divided into levels of access. At the top is the interbank foreign exchange market, which is made up of the largest commercial banks and securities dealers. Within the interbank market, spreads, which are the difference between the bid and ask prices, are razor sharp and not known to players outside the inner circle. The difference between the bid and ask prices widens (for example from 0 to 1 pip to 1–2 pips for currencies such as the EUR) as you go down the levels of access. This is due to volume. If a trader can guarantee large numbers of transactions for large amounts, they can demand a smaller difference between the bid and ask price, which is referred to as a better spread. The levels of access that make up the foreign exchange market are determined by the size of the "line" (the amount of money with which they are trading). The top-tier interbank market accounts for 51% of all transactions.[63] From there, smaller banks, followed by large multi-national corporations (which need to hedge risk and pay employees in different countries), large hedge funds, and even some of the retail market makers. According to Galati and Melvin, “Pension funds, insurance companies, mutual funds, and other institutional investors have played an increasingly important role in financial markets in general, and in FX markets in particular, since the early 2000s.” (2004) In addition, he notes, “Hedge funds have grown markedly over the 2001–2004 period in terms of both number and overall size”.[64] Central banks also participate in the foreign exchange market to align currencies to their economic needs.
Currencies are always traded in pairs, so the "value" of one of the currencies in that pair is relative to the value of the other. This determines how much of country A's currency country B can buy, and vice versa. Establishing this relationship (price) for the global markets is the main function of the foreign exchange market. This also greatly enhances liquidity in all other financial markets, which is key to overall stability.
Many currency pairs will move about 50 to 100 pips (sometimes more or less depending on overall market conditions) a day. A pip (an acronym for Point in Percentage) is the name used to indicate the fourth decimal place in a currency pair, or the second decimal place when JPY is in the pair. When the price of the EUR/USD moves from 1.3600 to 1.3650, that's a 50 pip move; if you bought the pair at 1.3600 and sold it at 1.3650 you'd make a 50-pip profit.
a MARKET engaged in the buying and selling of FOREIGN CURRENCIES. Such a market is required because each country involved in INTERNATIONAL TRADE and investment has its own domestic currency and this needs to be exchanged for other currencies in order to finance trade and capital transactions. This function is undertaken by a network of private foreign exchange dealers and a country's monetary authorities acting through its central banks.
The profit you made on the above theoretical trade depends on how much of the currency you purchased. If you bought 1,000 units (called a micro lot) each pip is worth $0.10, so you would calculate your profit as (50 pips * $0.10) = $5 for a 50 pip gain. If you bought a 10,000 unit (mini lot), then each pip is worth $1, so your profit ends up being $50. If you bought a 100,000 unit (standard lot) each pip is worth $10, so your profit is $500. This assumes you have a USD trading account.
An interesting observation is that the Forex Market Hours of the Tokyo and London sessions overlap for approximately 1 hour (varies for other European countries). You can (and probably should!) use this fact to your advantage. This means that all the crosses of European currencies and the JPY will have the highest volatility at the start of the European session. So if you are trading the GBPJPY you can simply carry out a few powerful trades between 8am-9am GMT, and then you are free for the day!
The second tier is the over-the-counter market. That's where companies and individuals trade. The OTC has become very popular since there are now many companies that offer online trading platforms. New traders, starting with limited capital, need to know more about forex trading. It’s risky because the forex industry is not highly regulated and provides substantial leverage.
While the forex market is clearly a great market to trade, I would note to all beginners that trading carries both the potential for reward and risk. Many people come into the markets thinking only about the reward and ignoring the risks involved, this is the fastest way to lose all of your trading account money. If you want to get started trading the Fx market on the right track, it’s critical that you are aware of and accept the fact that you could lose on any given trade you take.

Up until World War I, currencies were pegged to precious metals, such as gold and silver. But the system collapsed and was replaced by the Bretton Woods agreement after the second world war. That agreement resulted in the creation of three international organizations to facilitate economic activity across the globe. They were the International Monetary Fund (IMF), General Agreement on Tariffs and Trade (GATT), and the International Bank for Reconstruction and Development (IBRD). The new system also replaced gold with the US dollar as peg for international currencies. The US government promised to back up dollar supplies with equivalent gold reserves.
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.