You may need to convert your current currencies to a foreign country’s currency if you are going to visit that foreign country as that foreign country will not accept your currencies. When you are traveling in to a foreign country to llearn to day trade and when you are buying some goods from the local people, you will need to convert the currency. It is important to have a system that will convert one country’s currency in to another country’s currency. So you are now knowing the definition of the fx trading system. If an individual buys some currencies in some certain rates and then if he is able to sell these currencies at a bit higher prices then he can gain some profits from these trades.