The following keywords give you a short introduction to commodity trading.
Commodity exchanges are highly organised markets.
They are no longer chiefly physical markets, where deals are made out of warehouses, but they are places for the sale and purchase by contract of commodities available anywhere in the world and at any time. Actually, they have developped from spot markets to futures markets. Major world commodity markets are in London, Chicago, New York, Kansas City, Minneapolis, Winnipeg, Amsterdam, Sydney and Singapore. Some of the commodity exchanges have recently branched out into currency trading. Trading on commodity exchanges is highly standardised.