When you trade forex, you're effectively borrowing the first currency in the pair to buy or sell the second currency. With a US$5-trillion-a-day market, the liquidity is so deep that liquidity providers—the big banks, basically—allow you to trade with leverage. To trade with leverage, you simply set aside the required margin for your trade size. If you're trading 200:1 leverage, for example, you can trade £2,000 in the market while only setting aside £10 in margin in your trading account. For 50:1 leverage, the same trade size would still only require about £40 in margin. This gives you much more exposure, while keeping your capital investment down.
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.

Secondly, a larger return is needed on your remaining capital to retrieve any lost capital from the initial losing trade. If a trader loses 50% of their capital, it will take a 100% return to bring them back to the original capital level. Losing large chunks of money on single trades or on single days of trading can cripple capital growth for long periods of time.

Currency futures contracts are contracts specifying a standard volume of a particular currency to be exchanged on a specific settlement date. Thus the currency futures contracts are similar to forward contracts in terms of their obligation, but differ from forward contracts in the way they are traded. In addition, Futures are daily settled removing credit risk that exist in Forwards.[78] They are commonly used by MNCs to hedge their currency positions. In addition they are traded by speculators who hope to capitalize on their expectations of exchange rate movements.

Despite being able to trade 24 hours a day, 5 days a week, you shouldn’t (Forex trading is not quite 24.7). You should only trade a forex pair when it’s active, and when you’ve got enough volume. Trading forex at weekends will see small volume. Take GBP/USD for example, there are specific hours where you have enough volatility to create profits that are likely to negate the bid price spread and commission costs.
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.

To start, you must keep your risk on each trade very small, and 1% or less is typical. This means if you have a $3,000 account, you shouldn't lose more than $30 on a single trade. That may seem small, but losses do add up, and even a good day-trading strategy will see strings of losses. Risk is managed using a stop-loss order, which will be discussed in the Scenario sections below.
None of the models developed so far succeed to explain exchange rates and volatility in the longer time frames. For shorter time frames (less than a few days), algorithms can be devised to predict prices. It is understood from the above models that many macroeconomic factors affect the exchange rates and in the end currency prices are a result of dual forces of supply and demand. The world's currency markets can be viewed as a huge melting pot: in a large and ever-changing mix of current events, supply and demand factors are constantly shifting, and the price of one currency in relation to another shifts accordingly. No other market encompasses (and distills) as much of what is going on in the world at any given time as foreign exchange.[71]
U.S. President, Richard Nixon is credited with ending the Bretton Woods Accord and fixed rates of exchange, eventually resulting in a free-floating currency system. After the Accord ended in 1971,[31] the Smithsonian Agreement allowed rates to fluctuate by up to ±2%. In 1961–62, the volume of foreign operations by the U.S. Federal Reserve was relatively low.[32][33] Those involved in controlling exchange rates found the boundaries of the Agreement were not realistic and so ceased this[clarification needed] in March 1973, when sometime afterward[clarification needed] none of the major currencies were maintained with a capacity for conversion to gold[clarification needed], organizations relied instead on reserves of currency.[34][35] From 1970 to 1973, the volume of trading in the market increased three-fold.[36][37][38] At some time (according to Gandolfo during February–March 1973) some of the markets were "split", and a two-tier currency market[clarification needed] was subsequently introduced, with dual currency rates. This was abolished in March 1974.[39][40][41]
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.