The value of a country's currency depends on whether it is a "free float" or "fixed float". Free floating currencies are those whose relative value is determined by free market forces, such as supply / demand relationships. A fixed float is where a country's governing body sets its currency's relative value to other currencies, often by pegging it to some standard. Free floating currencies include the U.S. Dollar, Japanese Yen and British Pound, while examples of fixed floating currencies include the Chinese Yuan and the Indian Rupee.
National central banks play an important role in the foreign exchange markets. They try to control the money supply, inflation, and/or interest rates and often have official or unofficial target rates for their currencies. They can use their often substantial foreign exchange reserves to stabilize the market. Nevertheless, the effectiveness of central bank "stabilizing speculation" is doubtful because central banks do not go bankrupt if they make large losses as other traders would. There is also no convincing evidence that they actually make a profit from trading.
For instance, if you opened a long trade on the GBP/USD currency pair, and the pair increased in value, the price limit at which the trade should close (the stop loss) would climb alongside the price of the currency pair. If the value of the GBP/USD then started to fall, the trade would be closed as soon as it hit your stop loss, preserving any profits you had made beforehand.
Use a stop loss: A stop loss is tool that traders use to limit their potential losses. Simply put, it is the price level at which you will close a trade that isn't moving in your favour, thereby preventing any further losses as the market continues to move in that direction. You can also use a stop loss to conserve any profits you might have already made - the tool to achieve this is known as a 'trailing' stop loss, which follows the direction of the market.
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.
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.