Derivatives: contracts that ride on something else

The word derivative means exactly what it says: a contract whose value is derived from something else - the thing it tracks is called the underlying (the share, index, commodity or currency the contract is written on). You don't have to own the underlying to hold a derivative on it; you hold a contract whose payoff moves with its price.

People use them for two very different reasons. One is hedging - taking out a contract that gains when something you already own loses, so the two cancel and your risk is smaller. A farmer locking in a wheat price months ahead is hedging. The other is speculation - taking on risk on purpose to try to profit from a price move. The very same instrument can do either job; what changes is why you hold it and what else you own.

The four building blocks you'll meet again and again are forwards, futures, options and swaps. The first three are below; swaps (trading one stream of payments for another, like swapping a variable interest rate for a fixed one) are common between big institutions and behave the same way conceptually - a contract whose value rides on an underlying.

A forward is the simplest derivative: two parties agree now to trade something at a set price on a set future date. Whatever the market does in between, the deal is locked. If you agreed to buy at a price and the market ends up higher, you're better off than buying at the market; if it ends lower, you've overpaid - but in both cases you got certainty, which is often the whole point.

A future is a forward that's been standardised and listed on an exchange - same idea, but with fixed contract sizes and dates, traded through a central clearing house that sits between buyer and seller so neither has to trust the other directly. Australian futures trade on the ASX. Because both sides are obligated, a future is a symmetric contract: gains for one side are losses for the other, dollar for dollar.

The catch that surprises people is margin - you don't pay the full contract value up front, you post a deposit and top it up as the price moves against you (a margin call). That's where small price moves can demand large cash quickly, which leads straight into leverage, below.

An option is the right - but not the obligation - to buy or sell the underlying at a fixed price (the strike) before or on a set date. A call is the right to buy; a put is the right to sell. You pay for that right up front: the premium. Because you can simply walk away if it doesn't suit you, an option is asymmetric - and that asymmetry is the whole appeal.

Here's the durable maths for a bought option, and it never goes stale. Your maximum loss is the premium - the most you can lose is what you paid, because you can let the option lapse. For a bought call, your break-even is the strike plus the premium: the underlying has to clear the strike by enough to cover what you paid before you're ahead. Above that, your gain rises one-for-one with the price; in theory it's open-ended.

The mirror image matters just as much: the person who sold (wrote) that option took the premium up front, but carries the obligation if it's exercised - and a writer's potential loss can be far larger than the premium they pocketed. Selling options without owning the underlying is one of the faster ways to turn a small premium into a large bill, which is why it sits well beyond beginner territory.

The reason derivatives feel so powerful - and so dangerous - is leverage: controlling a large exposure for a small outlay. If a deposit of a fraction of the contract's value gives you the full price move, then a small percentage move in the underlying becomes a large percentage move in your money. That's true on the way up and, exactly as hard, on the way down. Leverage doesn't change the odds; it changes the size of the swings.

With a future or a CFD (a contract for difference - a leveraged contract that pays you the change in a price without owning the asset), losses are not capped at what you put in. A move against you can wipe out your deposit and trigger a margin call for more, so you can lose more than your initial stake. This is the single most important difference from buying a share outright, where the worst case is the share going to zero.

Because the risks are real and well documented, the regulator places limits on these products for everyday investors. ASIC caps how much leverage a retail client can be offered on CFDs and imposes other protections; it also publishes the blunt finding that most retail CFD traders lose money. The current cap and the latest data live on Moneysmart - read ASIC's CFD warning before going near one.

Derivatives can feel like a trading-screen thing, but the underlying idea - a contract whose value rides on another price - shows up in ordinary life. Your employee share options are exactly an option: the right to buy company shares at a set price later, worth something only if the share price clears that strike. A fixed-rate home loan is, in effect, your bank hedging interest-rate risk on your behalf and selling you the certainty.

Businesses hedge currency so a falling dollar doesn't blow up an import order; airlines hedge fuel so a price spike doesn't sink a season. Even an insurance policy is a cousin: you pay a premium for a payout that's triggered by an event - the same "pay now for a conditional payoff later" shape as an option. Spotting the pattern makes the jargon a lot less intimidating.