When a trader buys an options contract (either a Call or a Put), they have the rights given by the contract, and for these rights, they pay an upfront fee to the trader selling the options contract. This fee is called the options premium, which varies from one options market to another, and also within the same options market depending upon when the premium is calculated. The option's premium is calculated using three main criteria, which are as follows:
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).