This means that should the rate move against you, the value of your position deteriorates – this is an unrealized loss until the order is closed. LIMIT ORDERS A limit order is an order to buy or sell, but only when certain conditions included in the original trade instructions are fulfilled. What is Short, Long, Flat or Square in Forex Trading? It can be confusing in forex trading because you buy and sell in pairs. The first currency in a pair is known as the base currency sometimes. So if you are in long position for the pair "EUR/USD" this means you have bought the Euro (and automatically sold the Dollar).