Strike Price: This is the price at which you could buy or sell the underlying futures contract. The strike price is the insurance price. Think of it this way: The difference between a current market price and the strike price is similar to the deductible in other forms of insurance. As an example, a December $3.50 corn call allows you to buy a December futures contract at $3.50 anytime before the option expires. Most traders do not convert options to futures positions; they close the option position before expiration.
What if, instead of a home, your asset was a stock or index investment? Similarly, if an investor wants insurance on his/her S&P 500 index portfolio, they can purchase put options. An investor may fear that a bear market is near and may be unwilling to lose more than 10% of their long position in the S&P 500 index. If the S&P 500 is currently trading at $2500, he/she can purchase a put option giving the right to sell the index at $2250, for example, at any point in the next two years.
For instance, it is possible to construct an option strategy in the futures markets that is affordable without sacrificing the odds of success...but with the convenience comes theoretically unlimited risk. This is easier than it sounds, similar to the way you would borrow money to pay for a house or a car, you can borrow money from the exchange to pay for long commodity option trades. There are an unlimited number of combinations of self-financed trades but they are typically going to involve more short options than long options, or at least as much premium collected on the sold options than that paid for the longs. In essence, the money brought in through the sale of the short options goes to pay for the futures options that are purchased. The result is a relatively close-to-the-money option with little out of pocket expense but theoretically unlimited risk beyond the strike price of the naked short options.
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).