See also Commodities Prices
A commodity is a product that is sold without differentiation by all suppliers. For example, an ounce of gold is the same as any other ounce of gold, regardless of the seller. As a result, commodities tend to trade at a single market price, often with narrow margins.
Often, commodities are basic resources and agricultural products such as iron ore, crude oil, coal, ethanol, sugar, soybeans, aluminum, rice, wheat, gold and silver, but they can also be something as complex as a freight contract, a personal computer or carbon emissions.