Anybody can trade at global foreign exchange market.

You can trade national currency of any country at global FOREX market. To be more precise, here you can exchange one currency to another according to some proportion. Such exchange proportion is called exchange rate. And the two currencies participating in such exchange are shown one by one and called the currency pair. Thus, FOREX trading can be performed for various currency pairs. E.g. euro-dollar (EURUSD), or pound-dollar (GBPUSD) etc.