In Economics, a commodity is a marketable item produced to satisfy wants or needs. The commodity is generally Fungible (Fungibility is the property of a good or commodity whose individual units are capable of being substituted in place of one another). For example, since one ounce of pure gold is equivalent to any other ounce of pure gold, gold is fungible. Other fungible goods are Crude oil, steel, iron ore, currencies, precious metals, alloy and non-alloy metals.
Trading in commodity futures contracts can be very risky for the inexperienced. The high degree of leverage used with commodity futures can amplify gains, but losses can be amplified as well. If a futures contract position is losing money, the broker can initiate a margin call, which is a demand for additional funds to shore up the account. Further, the broker will usually have to approve an account to trade on margins before they can enter into contracts.
For example, a plastics producer could use commodity futures to lock in a price for buying natural gas by-products needed for production at a date in the future. The price of natural gas—like all petroleum products—can fluctuate considerably, and since the producer requires the natural gas by-product for production, they are at risk of cost increases in the future.
For example: A steel manufacturer importing coal from Australia currently and in order to reduce the volatility of changes in prices he always hedges the coal purchases on a 3 monthly forward contract where he agrees with the seller on day one of financial quarter to supply coal at defined price irrespective of price movements during quarter. So in this case, the contract is forward/future and buyer has an intention to buy the goods and no intention of making profit from price changes.
When buying or selling options, the investor or trader has the right to exercise that option at any point up until the expiration date - so simply buying or selling an option doesn't mean you actually have to exercise it at the buy/sell point. Because of this system, options are considered derivative securities - which means their price is derived from something else (in this case, from the value of assets like the market, securities or other underlying instruments). For this reason, options are often considered less risky than stocks (if used correctly).