It is the deliberate downward adjustment to a country's official exchange rate relative to other currencies. In a fixed exchange rate regime, only the decision by a country's government (i.e central bank) can alter the official value of the currency. This is the opposite of "revaluation". There are two major effects of a currency devaluation. First, devaluation makes a country's exports relatively less expensive for foreigners and second, it makes foreign products relatively more expensive for domestic consumers, discouraging imports. As a result, this may help to reduce a country's trade deficit.