Decide whether you think a commodity will sell for more or for less at some designated time in the future, then buy either a “put” or a “call” option. For example, you think that corn will cost more three months from now than it does now, so you will buy a “call” option on 100 bushels of corn which, in effect, locks in the cost of that commodity. Before the option expires, hopefully the price will go up, so your option will be worth more. Conversely, you will buy a “put” option if you think the price of the commodity will be less than it is today.

Puts are more or less the mirror image of calls. The put buyer expects the price to go down. Therefore, he pays a premium in the hope that the futures price will drop. If it does, he has two choices: (1) He can close out his long put position at a profit since it will be more valuable; or (2) he can exercise and obtain a profitable short position in the futures contract since the strike price will be higher than the prevailing futures price.

You also can limit your exposure to risk on stock positions you already have. Let’s say you own stock in a company but are worried about short-term volatility wiping out your investment gains. To hedge against losses, you can buy a “put” option that gives you the right to sell a particular number of shares at a predetermined price. If the share price does indeed tank, the option limits your losses, and the gains from selling help offset some of the financial hurt.
A call option is a contract that gives the investor the right to buy a certain amount of shares (typically 100 per contract) of a certain security or commodity at a specified price over a certain amount of time. For example, a call option would allow a trader to buy a certain amount of shares of either stocks, bonds, or even other instruments like ETFs or indexes at a future time (by the expiration of the contract).