The possibility of losing your investment is high, so it is advisable to only use risk capital (money that you can afford to lose) when engaging in Forex trading. The Forex market offers high levels of leverage to traders. Leverage has both the possibility of high returns and high losses, and should only be used with discretion. Be disciplined and don't be tempted to overtrade.
Determine the profits required to cover any losses: Along with calculating your risks before any trade, it's also worth calculating how much you would need to make to regain those funds in any future trade. It's often harder to earn money back than it is to lose it, simply because your remaining investment pool is smaller, which means you have to make a larger profit (percentage wise) to break even.
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.
Intra-day, a trader must also accept what the market provides at its various intervals. For example, markets are typically more volatile at the start of the trading day, which means specific strategies used during the market open may not work later in the day. It may become quieter as the day progresses and a different strategy can be used. Toward the close, there may be a pickup in action and yet another strategy can be used. If you can accept what is given at each point in the day, even it does not align with you expectations, you are better positioned for success.
The number quoted for these prices is based on the current exchange rate of the currencies in the pair, or how much of the second currency you would get in exchange for one unit of the first currency (for instance, if 1 EUR could be exchanged for 1.68 USD, the bid and ask price would be on either side of this number). Learn more about Forex quotes in this article: Understanding and Reading Forex Quotes.
The foreign exchange market is unique for several reasons, mainly because of its size. Trading volume in the forex market is generally very large. As an example, trading in foreign exchange markets averaged $5.1 trillion per day in April 2016, according to the Bank for International Settlements, which is owned by 60 central banks and is used to work in monetary and financial responsibility. 

Unless you understand the code it's written in, you're probably not going to be able to adapt your EA to work with those changes. If you are one of the many traders who believe that an EA would outperform the market, then perhaps you should give it a try with the MetaTrader Supreme Edition plugin. And perhaps best of all, we offer EAs free of charge for traders!
Reliability: Is the trading platform reliable enough for you to achieve the trading results you want? Being able to rely on the accuracy of prices quoted, the speed of data being transferred, and fast order execution is essential to being able to trade Forex successfully, particularly if you plan to use very short-term strategies like scalping. The information must be available in real time, and the platform must be available at all times when the Forex market is open. This ensures that you can take advantage of any opportunities that may present themselves.
Traders who understand indicators such as Bollinger bands or MACD will be more than capable of setting up their own alerts. But for the time poor, a paid service might prove fruitful. You would of course, need enough time to actually place the trades, and you need to be confident in the supplier. It is unlikely that someone with a profitable signal strategy is willing to share it cheaply (or at all). Beware of any promises that seem too good to be true.
Similarly, if you wanted to purchase 3,000 USD with Euros, that would cost 2,570 EUR. With a leverage rate of 1:30, however, you could access 3,000 USD worth of the EUR/USD currency pair as a CFD with just 100 USD. The best part, however, is that the size of the potential profit a trader could make is the same as if they had invested in the asset outright. The risk here is that potential losses are magnified to the same extent as potential profits.
In 1876, something called the gold exchange standard was implemented. Basically it said that all paper currency had to be backed by solid gold; the idea here was to stabilize world currencies by pegging them to the price of gold. It was a good idea in theory, but in reality it created boom-bust patterns which ultimately led to the demise of the gold standard.
Spread: The spread is the difference between a currency pair's bid and ask price. For the most popular currency pairs, the spread is often low - sometimes even less than a pip! For pairs that aren't traded as frequently, the spread tends to be much higher. Before a Forex trade becomes profitable, the value of the currency pair must cross the spread.

International parity conditions: Relative purchasing power parity, interest rate parity, Domestic Fisher effect, International Fisher effect. Though to some extent the above theories provide logical explanation for the fluctuations in exchange rates, yet these theories falter as they are based on challengeable assumptions [e.g., free flow of goods, services and capital] which seldom hold true in the real world.

These cover the bulk of countries outside Europe. Forex brokers catering for India, Hong Kong, Qatar etc are likely to have regulation in one of the above, rather than every country they support. Some brands are regulated across the globe (one is even regulated in 5 continents). Some bodies issue licenses, and others have a register of legal firms.

During the 15th century, the Medici family were required to open banks at foreign locations in order to exchange currencies to act on behalf of textile merchants.[10][11] To facilitate trade, the bank created the nostro (from Italian, this translates to "ours") account book which contained two columned entries showing amounts of foreign and local currencies; information pertaining to the keeping of an account with a foreign bank.[12][13][14][15] During the 17th (or 18th) century, Amsterdam maintained an active Forex market.[16] In 1704, foreign exchange took place between agents acting in the interests of the Kingdom of England and the County of Holland.[17]
"Buy the rumor, sell the fact": This market truism can apply to many currency situations. It is the tendency for the price of a currency to reflect the impact of a particular action before it occurs and, when the anticipated event comes to pass, react in exactly the opposite direction. This may also be referred to as a market being "oversold" or "overbought".[75] To buy the rumor or sell the fact can also be an example of the cognitive bias known as anchoring, when investors focus too much on the relevance of outside events to currency prices.

Experts say that forex is a zero-sum game. That means that someone always loses commensurate to someone else’s win — that’s how the game is played. When you add in costs and fees associated with running a forex account and making trades, you enter negative-sum territory. That said, shrewd trading moves can pay out. Substantially. If you have the time and interest required to learn to identify patterns in price fluctuations and execute far-sighted trades, you will make wins on the forex market. That said, the most thoughtful strategy is also liable to bring about loss. Don’t trade more than you can afford to lose.

Forex trading is governed by the National Futures Association, and they routinely check brokerages for financial irregularities, hidden or overly high fees, and scams. A key point of comparison between forex brokerages is their regulatory approval status with the NFA. Because the forex market and its major players move rapidly, it’s wise to regularly check on that status via the NFA’s Status Information Center. Increased regulation (coupled with higher capital requirements) continue to force forex brokers to leave the playing field, and one side effect is that it’s increasingly easy to find the best out of a constrained number of options.
Currencies are traded against one another in pairs. Each currency pair thus constitutes an individual trading product and is traditionally noted XXXYYY or XXX/YYY, where XXX and YYY are the ISO 4217 international three-letter code of the currencies involved. The first currency (XXX) is the base currency that is quoted relative to the second currency (YYY), called the counter currency (or quote currency). For instance, the quotation EURUSD (EUR/USD) 1.5465 is the price of the Euro expressed in US dollars, meaning 1 euro = 1.5465 dollars. The market convention is to quote most exchange rates against the USD with the US dollar as the base currency (e.g. USDJPY, USDCAD, USDCHF). The exceptions are the British pound (GBP), Australian dollar (AUD), the New Zealand dollar (NZD) and the euro (EUR) where the USD is the counter currency (e.g. GBPUSD, AUDUSD, NZDUSD, EURUSD).
Unlike stock markets, which can trace their roots back centuries, the forex market as we understand it today is a truly new market. Of course, in its most basic sense - that of people converting one currency to another for financial advantage - forex has been around since nations began minting currencies. But the modern forex markets are a modern invention. 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.