EUR / USD

In this example, the base currency is the euro, and thus the principle of "the buy / sell. If you think the U.S. economy continues to weaken, the dollar is bad, is it a BUY EUR / USD order. For this you bought for the expectation that they will reach the U.S. dollar. If you think theU.S. economy is strong and the euro will weaken the U.S. dollar want to execute SELL EUR / USD order. So you have sold the euro, provided that they belong to the U.S. dollar.