In terms of valuing option contracts, it is essentially all about determining the probabilities of future price events. The more likely something is to occur, the more expensive an option would be that profits from that event. For instance, a call value goes up as the stock (underlying) goes up. This is the key to understanding the relative value of options.
Investing with options— an advanced trader will tell you— is all about customization. Rewards can be high — but so can the risk— and your choices are plenty. But getting started isn’t easy, and there is potential for costly mistakes. Here’s a brief overview of option trading that cuts through the jargon and gets right to the core of this versatile way to invest.

Options trading may seem overwhelming, but they're easy to understand if you know a few key points. Investor portfolios are usually constructed with several asset classes. These may be stocks, bonds, ETFs, and even mutual funds. Options are another asset class, and when used correctly, they offer many advantages that trading stocks and ETFs alone cannot.
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.
The fee you are paying to buy the call option is called the premium (it's essentially the cost of buying the contract which will allow you to eventually buy the stock or security). In this sense, the premium of the call option is sort of like a down-payment like you would place on a house or car. When purchasing a call option, you agree with the seller on a strike price and are given the option to buy the security at a predetermined price (which doesn't change until the contract expires).