What an Option Is
An options contract is a deal between two people about a future price. That is the entire idea. Everything else is detail.
Start with the contract
An option is an agreement between a buyer and a seller. The buyer pays a small amount of money today (the premium) for the right to buy or sell a specific asset at a specific price (the strike) on or before a specific date (the expiry).
That is it. The whole structure is a paid right. The buyer can use it. The buyer can ignore it. The seller has no such choice. The seller took the money up front and now has to honor the deal if the buyer asks.
Why this asymmetry exists
The buyer is paying for optionality. They want to lock in a price without committing to the trade. If the market moves their way, they use the option. If it moves against them, they walk away and lose only the premium.
The seller is selling that flexibility. In exchange they collect the premium up front. Their hope is that the buyer never uses the right, and the premium becomes pure profit. Their fear is that the buyer does use it, and the loss can be large.
Two types of right
There are two kinds of options. A call is the right to buy. A put is the right to sell. That is the whole taxonomy. Every options strategy in existence is built out of calls and puts in some combination.
If you think a stock is going up, you buy a call. The call gives you the right to buy it later at today's strike, no matter how high it goes. If you think a stock is going down, you buy a put. The put gives you the right to sell it at today's strike, no matter how far it falls.
A concrete example
Suppose SPY is trading at $500 today. You think it will rise. You buy a call with a strike of $510 expiring in one month. The call costs $4 per share. Standard equity options control 100 shares per contract, so the actual cash outlay is $400.
Three things can happen by expiry:
- SPY ends below $510. Your call expires worthless. You lose the $400.
- SPY ends at $514. Your call is worth $4 per share at expiry. You break even.
- SPY ends at $530. Your call is worth $20 per share. You collect $2,000, a gain of $1,600 on a $400 outlay.
The buyer's loss is capped at the premium. The buyer's gain is unbounded. The seller of that call has the mirror image.
Why options exist at all
Options were not invented for speculation. They exist because there is real demand to transfer risk between people who do not want to hold it and people who are willing to be paid to hold it.
A farmer who wants to lock in a sale price for a crop they will harvest in six months can buy a put. A company that needs to buy oil next quarter can buy a call to cap their cost. The speculation came later. The risk transfer came first.
What you carry forward from this lesson
- An option is a paid right, not an obligation, for the buyer.
- An option is an obligation, not a right, for the seller.
- Calls give the right to buy. Puts give the right to sell.
- Premium, strike, expiry, and the underlying are the four numbers that define every option.
- The buyer has bounded loss and open-ended gain. The seller has the mirror.