# Derivatives: Futures, Options & Greeks

Szymon Kopyciński · 23 September 2026



## 1. Futures and forwards

### Forward

A contract agreeing today to buy or sell something at a specified price on a future date.

Forwards are traded OTC.

### Futures contract

A standardised contract to buy or sell an underlying asset at a specified price on a future date.

Futures are exchange-traded, centrally cleared and marked to market daily.

### Expiry

The date on which a derivative contract expires.

### Contract size

The amount of underlying exposure represented by one derivative contract.

### Front month

The futures contract with the nearest expiry.

It is usually, but not always, the most liquid contract.

### Roll

Closing a position in an expiring futures contract and opening an equivalent position in a later expiry.

### Contango

A futures curve where later-dated contracts trade at higher prices than nearer-dated contracts.

### Backwardation

A futures curve where later-dated contracts trade at lower prices than nearer-dated contracts.

### Mark-to-market

For futures, gains and losses are settled daily through variation margin paid to or received from the clearing house.

## 2. Options

### Option

A derivative giving its holder the right, but not the obligation, to buy or sell an underlying asset at a specified price.

### Call option

An option giving the holder the right to buy the underlying at the strike price.

### Put option

An option giving the holder the right to sell the underlying at the strike price.

### Strike

The price at which the underlying may be bought or sold under the option contract.

### Premium

The price paid to buy an option.

### Expiration / Expiry

The date on which the option ceases to exist.

### Exercise

Using the right granted by an option.

### European option

An option that can only be exercised at expiry.

The name does not refer to where the option trades.

### American option

An option that can be exercised at any time up to and including expiry.

As with European options, the name does not refer to geography.

### ITM / In-the-money

An option with positive intrinsic value.

For a call: $S > K$. For a put: $S < K$.

Here $S$ is the underlying price and $K$ is the strike.

### ATM / At-the-money

An option whose strike is approximately equal to the current underlying price.

### OTM / Out-of-the-money

An option with no intrinsic value because its strike is on the unfavourable side of the underlying price.

For a call: $S < K$. For a put: $S > K$.

### Intrinsic value

The value an option would have if exercised immediately.

For a call:

$$ \max(S - K, 0) $$

For a put:

$$ \max(K - S, 0) $$

### Time value

The portion of an option's price above its intrinsic value.

It reflects the chance that market movements before expiry make the option more valuable.

### Implied volatility / IV

The volatility that makes an option-pricing model match an option's observed market price.

Traders frequently quote options in terms of implied volatility rather than price.

## 3. The Greeks

### Delta

The sensitivity of an option's value to a small change in the underlying price.

$$ \Delta = \frac{\partial V}{\partial S} $$

A call has delta between 0 and 1. A put has delta between −1 and 0.

### Gamma

The sensitivity of delta to changes in the underlying price.

$$ \Gamma = \frac{\partial^2 V}{\partial S^2} $$

High gamma means an option's directional exposure changes quickly as the underlying moves.

### Vega

The sensitivity of an option's value to changes in implied volatility.

Despite the name, vega is not a Greek letter.

### Theta

The sensitivity of an option's value to the passage of time.

Long options usually have negative theta because their time value decays as expiry approaches.

### Rho

The sensitivity of an option's value to interest rates.

### Volatility smile

A pattern where implied volatility varies by strike rather than remaining constant, rising for strikes further from the money.

### Volatility skew

An asymmetric relationship between implied volatility and strike.

Equity index options typically show higher implied volatility for downside strikes.

### Volatility surface

Implied volatility across both strike and time to expiry.

Part of [Glossary Index](/blog/glossary-index) · Previous: [Backtesting & Validation](/blog/glossary-index/glossary-backtesting-and-validation) · Next: [Trading Systems & Market Connectivity](/blog/glossary-index/glossary-trading-systems-market-conn)
