A currency, usually from a highly industrialised country, that is widely accepted around the world. in wwhich investors have full confidence and which is freely convertible any where ... like USD or British Pound Sterling.
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Hard currency (also known as a safe-haven currency or strong currency), in economics, refers to a globally traded currency that is expected to serve as a reliable and stable store of value. Factors contributing to a currency's hard status might include the long-term stability of its purchasing power, the associated country's political and fiscal condition and outlook, and the policy posture of the issuing central bank.