What Currencies Trade in Forex?

Although some retail dealers trade exotic currencies such as the Thai baht or the Czech koruna, the majority of dealers trade the seven most liquid currency pairs in the world, which are the four "majors":
EUR/USD (euro/dollar)
USD/JPY (dollar/Japanese yen)
GBP/USD (British pound/dollar)
USD/CHF (dollar/Swiss franc)
and the three commodity pairs:
AUD/USD (Australian dollar/dollar)
USD/CAD (dollar/Canadian dollar)
NZD/USD (New Zealand dollar/dollar)
These currency pairs along with their various combinations (such as EUR/JPY, GBP/JPY, and EUR/GBP) account for more than 95% of all speculative trading in FX. Given the small number of trading instruments—only 18 pairs and crosses are actively traded—the FX market is far more concentrated than the stock market.