Etymology
The word commodity came into use in English in the 15th century, from the French commodité, “amenity, convenience”.
Going further back, the French word derives from the Latin commoditas, meaning “suitability, convenience, advantage”.
The Latin word commodus (from which English gets other words including commodious and accommodate) meant variously “appropriate”, “proper measure, time, or condition”, and “advantage, benefit”.
Types of commodity
The term commodity is specifically used for an economic good or service when the demand for it has no qualitative product differentiation across a Market (economics).
In other words, a commodity good or service has full or partial but substantial fungibility; that is, the market treats its instances as equivalent or nearly so with no regard to who produced them. As the saying goes, “From the taste of wheat, it is not possible to tell who produced it, a Serfdom in Russia, a French peasant or an English capitalist.” Petroleum and copper are other examples of such commodities
their supply and demand being a part of one universal market. Items such as stereo systems, on the other hand, have many aspects of product differentiation, such as the brand, the user interface and the perceived quality.
The demand for one type of stereo may be much larger than demand for another.
In contrast, one of the characteristics of a commodity good is that its price is determined as a function of its market as a whole. Well-established physical commodities have actively traded spot market|spot and Derivative (finance)|derivative markets. Generally, these are basic resources and agricultural products such as iron ore, sugar, rice. Soft commodities are goods that are grown, while hard commodities are ones that are extracted through mining.
There is another important class of energy commodities which includes electricity, gas, coal, and oil. Electricity has the particular characteristic that it is usually uneconomical to store; hence, electricity must be consumed as soon as it is processed.