What is the difference between a call and a put option?

A call option gives the buyer the right to buy shares at a fixed strike price, used when expecting the stock to rise. A put option gives the buyer the right to sell shares at a fixed strike price, used when expecting the stock to fall. The seller of either contract takes the opposite obligation in exchange for collecting the premium.

What happens to an option as expiration approaches?

An option loses extrinsic (time) value as expiration nears, a process called time decay. An out-of-the-money option can lose most of its value in the final days before expiration even if the underlying stock barely moves.

June 1, 2026·9 min read·By WideRadar

Options Trading Basics: Calls, Puts, and Key Terms Explained

Q: Is buying options less risky than buying stock?

Buying a call or put has a defined maximum loss equal to the premium paid, which is one appeal. However, most bought options expire worthless if the stock doesn't move enough in the right direction in time, so the probability of a full loss is often higher than with owning stock outright.

Options let you control stock exposure with defined risk — but the terminology trips up most beginners. Here's what calls, puts, strikes, and expiration actually mean before you place a trade.

An option is a contract that gives its buyer the right, but not the obligation, to buy or sell 100 shares of a stock at a fixed price before a set date. Options can be used to speculate on direction with defined risk, generate income, or hedge an existing position — but they carry their own vocabulary that's worth learning before risking real money.

Calls vs. puts

A call option gives the buyer the right to buy shares at a fixed price — you buy calls when you expect the stock to rise. A put option gives the buyer the right to sell shares at a fixed price — you buy puts when you expect the stock to fall. The seller (or "writer") of the option takes the opposite side and collects a premium up front in exchange for taking on that obligation.

Strike price and expiration

The strike price is the fixed price at which the option can be exercised. The expiration date is the last day the contract is valid. An option is "in the money" when exercising it would be profitable relative to the current stock price, and "out of the money" otherwise. As expiration approaches, an out-of-the-money option loses value — a process called time decay — even if the stock doesn't move.

Premium: the price of the contract

The premium is what the buyer pays and the seller receives, quoted per share and multiplied by 100 (one contract = 100 shares). Premium is made up of intrinsic value (how far in the money the option already is) plus extrinsic value (time remaining and implied volatility). Understanding implied volatility is essential once you move beyond the basics, since it drives a large share of an option's price.

The defined-risk appeal — and the real risks

Buying a call or put has a defined maximum loss: the premium paid, no more. That's the main appeal over buying or shorting stock outright, where losses (on a short) can theoretically be unlimited. But options add complexity: time decay works against buyers every single day, and most options expire worthless if the stock doesn't move enough, in the right direction, before expiration. Selling options (rather than buying them) flips this dynamic and introduces its own, often larger, risks.

Where to start

Most experienced traders recommend beginners paper-trade options first, stick to buying (not selling) calls and puts on liquid, well-known stocks, and size positions so a total loss of the premium is a survivable, planned-for outcome rather than a portfolio-threatening one.

Sources & References