Currency pairs are just that, pairs. One vs another. EURUSD or USDJPY The prefix is the the first currency in the pair and the suffix the second of the pair. Look at a EURUSD and a USDCHF chart at the same time. Opposite directions. Why? Because look at the prefeix and suffix of the pair. eurUSD $ is suffix, USDchf $ is prefix. Also a clever way of trading other pairs. For example if you look at EURGBP you can gauge whether EUR is stronger or weaker than pound. Then look at USDJPY and see whether USD is stronger or weaker than Yen. then trade EURUSD or GBPUSD or GBPJPY or EURJPY accordingly. Example - EURGBP is going up. That's Euro strength and Pound weakness USDJPY is also going up. That's Dollar strength and Yen weakness. So from this we can say that EURUSD will probably go nowhere as both the euro and the usd are strong. Better to look for shorting GBPUSD or going long EURJPY