Foreign exchange derivative is a type of investment that involves investments in two or more different types of currencies. It is a way to try to make money by buying one currency when it is cheap and selling it when it is more expensive. For example, if a person buys 10 euros (the currency of the European Union) when it is worth $14 and then sells it when it is worth $15, they would make a profit of $1. The person is not actually buying anything physical like they would when they buy something in a store, but they are buying and selling money.