An option is a contract that gives its holder the right, but not the obligation, to buy or sell an underlying asset at a set strike price on or before an expiration date. A call is a right to buy; a put is a right to sell. The buyer pays a premium to the seller, who takes on the obligation if the contract is exercised. That simple structure produces a surprisingly wide range of payoffs, which is why options are used for hedging, for generating income, and for speculation.
The premium itself has two parts. Intrinsic value is what the option would be worth if exercised right now; time value is everything else, and it shrinks as expiration approaches. How the price responds to the stock price, to the passage of time, and to changes in expected volatility is summarised by the Greeks: delta, gamma, theta, vega and rho. Learning to read them is the quickest way to understand why an option moved when the underlying stock did not.
Implied volatility is the market’s price for uncertainty. It is backed out of option prices rather than observed directly, and it tends to differ across strikes and expirations, which is where concepts like skew and the smile come from. The VIX applies the same idea to a basket of S&P 500 index options, which is why it is often called a fear gauge. Understanding implied volatility also explains why options can lose value after an event even when the stock moves the way a trader expected.
Strategies are combinations of calls, puts and sometimes the underlying shares. Some, such as covered calls and the wheel, are built around collecting premium; others, such as straddles and strangles, are built around volatility; defined-risk structures like iron condors cap both the possible gain and the possible loss. Each has trade-offs around breakevens, assignment, liquidity and taxes, and every one of them can lose money.
The guides below are grouped from first principles to strategy to market mechanics. If you are new, start with the basics and the Greeks before moving to strategies. Options involve risk and are not suitable for every investor; the Options Clearing Corporation publishes the booklet “Characteristics and Risks of Standardized Options,” which is worth reading before you trade.
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Start here
The two foundational explainers: what options are, and how their prices respond to the things that move them.
- Options 101: Calls, Puts, Strike, Expiration Explained — calls, puts, strike, expiration and intrinsic value from scratch
- Options Greeks Explained: Delta, Gamma, Theta, Vega — delta, gamma, theta, vega and rho, and what each one tells you
- Implied Volatility Explained: How Options Price Future Moves — how option prices embed expectations about future moves
Pricing and volatility
Where option prices come from and why they differ across strikes and dates.
- Black-Scholes Explained: How Options Are Priced — the model behind much of option pricing and its assumptions
- Volatility Skew and Smile Explained: Why OTM Puts Cost More — why out-of-the-money puts often cost more than equivalent calls
- The VIX Explained: How Wall Street’s Fear Gauge Works — how the VIX is built and how volatility products relate to it
Strategies
Common structures, how they pay off, and where they can go wrong.
- Covered Calls Explained: How They Work and When They Don’t — selling calls against shares you own, and the trade-offs
- The Wheel Strategy Explained: How the Options Cycle Works — cycling between cash-secured puts and covered calls
- Iron Condor Explained: How the 4-Leg Trade Actually Works — a four-leg, defined-risk trade and its breakevens
- Straddle vs. Strangle: How Volatility Options Trades Work — two ways to trade volatility, compared
- 0DTE Options Explained: How Same-Day Expirations Work — same-day expirations and how they behave
Exercise, assignment and settlement
The mechanics that matter once a position is open.
- Options Assignment Explained: Early Exercise and Pin Risk — early exercise, pin risk and what happens near expiration
- Index Options vs. Equity Options: Cash Settlement & Tax Rules — cash settlement and tax treatment compared with equity options
- Quad Witching Explained: What Happens on Expiration Friday — what happens on expiration Friday
Market behaviour and related instruments
How options activity connects to stock moves and to other derivatives.
- Gamma Squeeze Explained: Why GameStop Wasn’t One — how dealer hedging and options flow can amplify price moves
- Stock Warrants Explained: Why They Aren’t Just Long-Dated Calls — how warrants differ from long-dated calls
- Stock Index Futures Explained: Fair Value, Basis, and Pricing — fair value, basis and pricing of index futures
- Contango Explained: Why Commodity ETFs Lose to Spot Prices — why futures curves can erode returns for commodity funds
Related tools
- Options Payoff Visualizer — payoff diagrams for common option positions