In the foreign exchange market you can buy or sell one currency for another. When you buy a currency, you are "long" in that currency and when you sell a currency, you are "short" in that currency. Because the value of a currency is more or less strong compared to another, traders decide to buy or sell foreign currencies to generate profits because the objective is to generate a profit from its position .

Trader in the foreign exchange market is simple and negotiation mechanisms are virtually identical to those of other markets.
Because of the symmetry of currency transactions, you are always simultaneously long in one currency and short in another. An open position is a current position. As long as the position remains open, its value fluctuates according to market exchange rates.

To close your position, you make a negotiation equal and opposite in the same currency pair. For example, if you were long in the pair EUR / USD you can close this position then being short in pair EURO / USD (price prevailing document).