What are options in trading? The basics explained

Options are financial instruments that grant the right, but never the obligation, to buy or sell an asset at a price fixed in advance, before a certain date. They have a reputation as a shortcut to fast gains, but the reality is harsher: the US securities regulator writes that it is possible to lose all of your initial investment, and sometimes more. This guide explains the basics without unnecessary jargon, with the definitions from the reference documents and examples you can recalculate.

• An option is a right, not an obligation: you pay a premium to reserve that right.
• Only two types: the call (right to buy) and the put (right to sell).
• Time works against the buyer: an option's time value erodes as expiration approaches, even if the price doesn't move.
• The risk is not the same on both sides: the buyer can lose the whole premium, the seller of an uncovered call has no cap on the loss.

There's a reason options are so fascinating: with a modest starting stake, they give an exposure far larger than the amount committed. That's exactly what draws poorly prepared beginners toward an instrument whose mechanics and traps they don't understand. A stock can fall and recover later; an option has an end date, and if it expires out of the money, the premium paid is lost in full. Plain stock trading is a far gentler place to start.

This guide starts from the basics: what an option is, how its price is made up, why time works against the buyer, and what options are really used for, before frankly addressing why most beginner traders should stay away from them at first.

What an option is

An option is a contract that gives its buyer the right, but not the obligation, to buy or sell an underlying asset (a stock, an index, an exchange traded fund) at a predetermined price, called the strike price, on or before a given expiration date. That is the definition given by the SEC's investor bulletin 'An Introduction to Options', from the US securities regulator. In exchange for that right, the buyer pays the seller an amount called the premium, paid up front and non-refundable. The seller, for their part, commits to honoring the transaction if the buyer exercises the right.

On stocks, a contract generally represents 100 shares, and the premium is quoted per share. The SEC bulletin takes the example of a $2.20 premium: the contract costs $2.20 × 100 = $220, before commissions. In France, the AMF's study of the market for options on French stocks, published in July 2021, likewise notes that most of the time one contract gives the right to buy or sell the equivalent of 100 shares. It is a multiplier to keep in mind whenever you read a quote.

This asymmetry between buyer and seller is the core of the mechanism. The buyer has a right, never an obligation, and what they risk is the premium paid, all of it if the option expires out of the money. The seller has an obligation if assigned, and their risk can be far greater: the same bulletin writes that certain types of contracts can expose writers to unlimited potential losses. This distinction between the buyer's and the seller's risk profile is the first thing to absorb before touching options.

Call and put options: the two types

There are only two types of options, calls and puts, and more elaborate positions combine them. The Options Industry Council (OIC), the educational arm of the US options clearing house, sums it up in its page 'What is an Option?': buying a call gives the right to buy the underlying at the strike price on or before expiration, buying a put gives the right to sell it. A call option is therefore bought when a rise is expected, because it lets you buy at a price fixed in advance, and a put option when a fall is expected, because it lets you sell at a price fixed in advance.

Every option also has a seller on the other side. According to the same page, whoever sells a call as an opening transaction is obligated to sell the underlying at the strike price if assigned, and whoever sells a put is obligated to buy it. In both cases the seller collects the premium, and has no control over whether the contract is exercised.

Three expressions place the strike price relative to the market price. The OIC's page on leverage and risk defines them this way: a call is 'in the money' when its strike price is below the current price of the underlying, a put when its strike price is above it. The inverse is 'out of the money', and an option is 'at the money' when strike and market price are equal. In the money does not mean profitable: the gain still has to exceed the premium paid.

Where an option's price comes from: the premium

An option's price, the premium, breaks down into two elements. Intrinsic value is the amount by which the option is in the money: it only exists in that case, otherwise it's zero. Time value is whatever the premium is worth beyond that. The OIC's page on options pricing defines it as any premium in excess of intrinsic value before expiration, in other words what an investor is willing to pay on top.

Without going into the formulas, the same page lists six factors that weigh on the premium: the underlying price, the strike, the time until expiration, implied volatility, dividends and the interest rate, the last two having a lesser effect. The idea to remember: the more time remains and the higher the implied volatility, the more expensive the premium, for calls and puts alike. Conversely, as expiration approaches, time value melts away, a central phenomenon for understanding why an option does not behave like a stock.

Why time works against the buyer

This is the point that surprises people coming from stocks: an option's time value erodes as expiration approaches, even if the underlying asset's price doesn't move at all, all other things being equal. The phenomenon is called time decay, and it is not steady: the OIC's page on leverage and risk, cited above, writes that it increases rapidly in the last several weeks of an option's life. An option bought three months before its expiry therefore loses its time value slowly at first, then faster and faster.

Concretely, an option buyer doesn't just need to be right about price direction, they also need to be right about timing. The Options Industry Council's Long Call page says it plainly: being right about an anticipated rally does no good if it occurs after expiration, and the earlier and sharper the increase, the better for the call buyer. A trader who buys a call may therefore see the price climb as expected, but too slowly, and find that time decay has taken away more value than the rise created.

This decay has a name and a number: theta. It is one of the option Greeks, the measures that estimate how much the premium moves when price, time or implied volatility change.

Assignment risk

Exercising an option means invoking the right to buy or sell. The seller then receives an assignment notice, which obliges them to fulfil the contract at the strike price. The OIC's page on exercising options explains that the clearing house assigns the notice at random to a brokerage firm, which then assigns one of its customers who wrote that option, either at random or on a first-in-first-out basis, depending on the firm's method.

When exercise is possible depends on the option's style. An American-style option can be exercised at any time before expiration, a European-style option only at expiration. The AMF study cited above notes that the vast majority of French options traded are American: on Euronext, only 3% of the options traded in 2019 were European. The consequence for the seller of an American option: assignment can come before expiration, and the OIC page adds that once assignment is received, there is no alternative but to fulfil it.

Selling an option (rather than buying one) exposes you to a particular risk called assignment risk: if the option's buyer decides to exercise it, the seller is obligated to honor the transaction, ready or not. Selling a call without holding the underlying asset, a strategy called a naked call, exposes you to having to buy the asset at market price to deliver it at the strike. The OIC's page on the naked call writes that the maximum loss is unlimited, since there is no limit to how high a stock's price could rise, and calls it the most extreme form of option investment risk.

This risk explains why selling options is not open to every account. FINRA's page on options, from the body that oversees US brokers, points out that before you can trade options, your brokerage firm must approve your account for a specific level of options trading, since some strategies involve substantial risk. In the US, another constraint long weighed on frequent same-day round trips: the pattern day trader rule and its 25,000 dollar equity floor. It no longer applies in that form: FINRA's Regulatory Notice 26-10 has replaced it since June 4, 2026 with an intraday margin standard, and brokers have until October 20, 2027 to switch over. Even more conservative selling strategies, where the sold option is covered by an existing position in the underlying asset, require a solid understanding of the mechanism before being used seriously.

Cash secured put: selling a put with the cash set aside

A cash secured put is the covered version of selling a put. The Options Industry Council's page on the cash-secured put describes it as writing an at-the-money or out-of-the-money put option and simultaneously setting aside enough cash to buy the stock. It presents it primarily as a stock acquisition strategy for a price-sensitive investor: unlike a naked put writer, whose only goal is to collect premium income, the writer actually wants to acquire the stock through assignment. In the OIC's words, cash secured puts are a variation on the naked put, the main difference being that the funds for buying the stock have been set aside.

The arithmetic, on a constructed example before commissions: you sell one put with a strike of 60 for a premium of 2, and keep 60 × 100 = 6,000 in cash aside. The premium received, 2 × 100 = 200, is the maximum gain from the option itself. The breakeven is strike price minus premium, 60 − 2 = 58. If the stock is above 60 at expiration, the put expires worthless and you keep the 200. If the put is assigned, you buy 100 shares at 60, an effective price of 58 per share.

The name can mislead: the cash secures the purchase, not the result. The same page calls the maximum loss limited but substantial. If the stock became worthless, you would still be obligated to buy it at the strike, a loss of 58 × 100 = 5,800 in this example, and the OIC describes the premium earned as comparatively small compensation for accepting the large downside risk of a stock owner. Assignment is not guaranteed either: if the stock stays above the strike, you miss the purchase and keep only the premium. This describes how the position works; it is not a recommendation to use it.

Hedging vs speculation

Options are not only used to speculate. One of their uses is hedging, meaning protecting an existing portfolio against an adverse move. The OIC's page on the benefits and risks of options compares them to an insurance policy against a drop in stock prices: an investor worried about a decline in their shares can purchase puts, which give the right to sell at the strike price no matter how low the market price drops before expiration. The cost of that insurance is the premium, and the same page points out that returns are never guaranteed.

The other use, speculation, consists of using options to bet on a price direction with significant leverage, since a relatively small premium gives market exposure to the value of the whole contract. Leverage cuts both ways: the OIC's page on leverage and risk writes that if the underlying price does not move as anticipated during the lifetime of the option, leverage could magnify the percentage loss. The AMF study cited above draws the consequence: options investors must be informed and aware of the risks they are exposed to.

An illustrative example

Here is a constructed example, before commissions. A trader buys a call on a stock trading at 100, with a strike of 105 and expiration in thirty days, for a premium of 2. As the contract covers 100 shares, they pay 2 × 100 = 200. Their breakeven at expiration is 105 + 2 = 107, following the formula on the OIC page, strike plus premium. If the stock ends at 103, it has risen, but it stays below the strike: the option expires worthless and they lose the 200, their whole stake. If it ends at 110, the option is worth 5 and the profit is 5 − 2 = 3 per share, or 300.

The put is calculated as a mirror image. A put with a strike of 95 bought for 2 costs 200, and its breakeven is 95 − 2 = 93, the OIC's Long Put page giving the formula strike minus premium. At 90 at expiration, it is worth 5 and pays 300; above 95, it expires worthless and the 200 is lost. On the other side, the seller of each of these options collects 200, and that is the maximum gain. The seller of the uncovered call loses 300 if the stock ends at 110, and more with every point higher, with no cap. The seller of the put would lose at worst (95 − 2) × 100 = 9,300 if the stock fell to zero.

This example shows the difference with a plain stock purchase: on a stock you bought, a rise is enough to produce a gain, even a modest one. On an option, being right about direction isn't enough: the move has to go beyond the breakeven, and before expiration. It's this extra requirement that lets an option expire worthless even when its buyer's directional call turned out to be correct.

Why beginners should be wary

Options combine several sources of complexity rarely present together in other markets, a plain stock or a futures contract included: a direction to predict, a timing to respect, a time decay that works against the buyer continuously, and for the seller, an assignment risk that can far exceed the premium collected. Each of these elements needs to be understood separately before they can be intelligently combined into a coherent strategy.

That's why options are not the instrument to start with. The OIC's page on benefits and risks itself writes that they may not be appropriate for all investors. Learning first to master a simpler market, like stocks or forex, while building solid risk management discipline, sizing every entry with a position size calculator and keeping a rigorous trading journal, gives you a much safer foundation before venturing into an instrument where a single bad timing estimate can lose the whole premium paid.

On a stock, being wrong usually costs you dearly. On a poorly understood option, being wrong can cost you everything, and fast.

How Tradoshi helps if you trade options

If you're already comfortable with other markets and exploring options, Tradoshi lets you journal these trades with the same rigor as your other positions, so you can see clearly whether this instrument is actually paying off or quietly eating into your capital.

• Unified trading journal that accepts your options trades alongside your other markets.
• Per-instrument trading statistics to honestly compare your performance on options versus everything else, win rate included.
• R-multiple and expectancy computed automatically to judge your edge without relying on a feeling, on the same risk reward calculator logic as your other markets.
• Emotional check-in to spot whether the speed of options moves amplifies your stress or impulsivity.

How to calculate an option's profit

Calculating an option comes down to two questions: what the premium is worth, and what the position pays at expiration. The premium is paid up front and lost in full if the option expires out of the money; the profit is then the intrinsic value minus that premium. An option profit calculator runs exactly that subtraction, for a call or for a put, and equity traders simply add a column for the number of shares each contract covers.

Position type changes the label, not the arithmetic: long or short, call or put, the same subtraction runs underneath. What the arithmetic will not tell you is whether the trade was any good. A single option that pays does not make an edge, and judging that requires the same statistics as any other market, starting with P&L read across every position rather than one screenshot of a winner.

What separates a useful tool from a misleading one is not its number of fields but its honesty about what it refuses to compute. Delta, probability of profit and any valuation before expiration all require implied volatility, which a simple calculator does not hold; a tool that displays them anyway is guessing, and a guess printed as a number is worse than no number at all. The same applies to history: serious options backtesting needs the full option chain, and any options backtesting software holding only the underlying will produce clean results that are quietly wrong.

Frequently asked questions