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.
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).