What Is an Option? Calls and Puts Explained

In short

Options are contracts on 100 shares that grant the right, not the obligation, to buy (call) or sell (put) at a fixed price by a fixed date; your risk as a buyer is capped at the premium paid.

An option gives you the right — never the obligation — to buy or sell 100 shares of stock at a fixed price, by a fixed date.

Options are rights, not obligations

An option is a contract tied to 100 shares of stock. It locks in a price today — called the strike price — for a trade you can choose to make later, up until a set cutoff called the expiration date. A call is the right to buy at the strike price. A put is the right to sell at the strike price. You pay a small amount upfront — the premium — for that right, and nothing forces you to use it.

Every contract has two sides. The buyer pays the premium and holds the right. The seller collects that premium but takes on the obligation to follow through if the buyer decides to exercise — deliver 100 shares for a call, or buy 100 shares for a put.

That obligation — and what it's like to be on the hook for it — gets its own lesson on assignment.

The names make sense once you see the mechanics: a call lets you call shares away from someone at the strike price; a put lets you put (hand off) shares to someone at the strike price.

Worked example: a call and a put on the same stock

Fictional stock XYZ trades at $48. Here's what happens if you buy a call versus a put.

Call: $50 strike, 60 days out, $1.50 premium ($150 total)


Premium paid (100 × $1.50)	$150
Your right	Buy 100 shares of XYZ at $50, any time before expiration
If XYZ rises to $56	Worth exercising or selling — a $6 gap minus your $1.50 cost
If XYZ stays at $48 or falls	Not worth using; the option can expire worthless

Put: $46 strike, 60 days out, $1.30 premium ($130 total)


Premium paid (100 × $1.30)	$130
Your right	Sell 100 shares of XYZ at $46, any time before expiration
If XYZ falls to $40	Worth exercising or selling — a $6 gap minus your $1.30 cost
If XYZ stays at $48 or rises	Not worth using; the option can expire worthless

Same structure, opposite direction: a call pays off when the stock rises above the strike, a put pays off when it falls below the strike. Either way, if the stock doesn't cooperate, you simply let the option expire — your loss is capped at the premium you paid, never more.

Worth knowing up front: that cap doesn't make options buying gentle. Because time is working against the option even when the stock direction isn't, options buyers lose their entire premium far more often than stock owners lose their entire investment — a right that's never used is a total loss on that position, and "never used" is the most common outcome for a buyer who's slow or wrong.

Key takeaway: An option is a capped-risk bet on direction — you pay a small premium for the right to buy (call) or sell (put) at a fixed price, and you can never lose more than that premium.

Next up: the two numbers that define what a contract actually costs — strike price and premium.

This lesson is educational content explaining standard options mechanics, not personalized investment or trading advice.