Developed countries gradually moved to a market determined exchange rate and developing countries adopted either a system of pegged currency or a system of managed rate
The most traded currency pairs in the world are called the Majors. The list includes following currencies: Euro (EUR), US Dollar (USD), Japanese Yen (JPY), Pound Sterling (GBP), Australian Dollar (AUD), Canadian Dollar (CAD), and the Swiss Franc (CHF). These currencies follow free floating method of valuation.
the most active currency pairs are: EURUSD, USDJPY, GBPUSD, AUDUSD, CADUSD, USDCNY and USDCHF
The US Dollar reflects its substantial international role as 'investment' currency in many capital markets, 'reserve' currency held by many central banks, 'transaction' currency in many international commodity markets, 'invoice' currency in many contracts, and 'intervention' currency employed by monetary authorities in market operations to influence their own exchange rates.
The widespread trading of the US Dollar reflects its use as a 'vehicle' currency in foreign exchange transactions, a use that reinforces its international role in trade and finance.
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