Specie backed money is money distributed, normally as paper money, that is assigned value based on valuable minerals tied to the paper money. The idea is that with specie backed money, though the paper itself holds no true value, it represents whatever mineral is held in reserve, historically gold and silver. Holders of the paper money could theoretically exchange their bills for the gold or silver that it represented. This way, the money held a true value, while not being as bulky or tough to carry around as say gold, silver, or cows. Specie backed money has generally given way to fiat money, money that is not backed by any valuable resources. Today most currencies are fiat currencies, with values assigned by the governments issuing the bills, and holding no true values.