Options trading basics: what a call and a put actually are

An option is a contract that gives its buyer the right, but not the obligation, to buy or sell something at a fixed price before a fixed date. A call option is the right to buy; a put option is the right to sell. The buyer pays a price called the premium for that right, and can lose the entire premium. The seller receives the premium and takes on the obligation, and can lose far more.

Call and put option kya hai: the plain version

Call and put option kya hai means "what are call and put options". Start with an everyday version.

Suppose a flat is on sale for ₹50 lakh. You pay the builder ₹1 lakh for the right to buy it at ₹50 lakh any time in the next three months. If prices jump and the flat is worth ₹56 lakh, you exercise your right, buy at ₹50 lakh, and you are ahead by ₹5 lakh after the ₹1 lakh you paid. If prices fall to ₹45 lakh, you simply walk away. You lost the ₹1 lakh and nothing more. The builder kept ₹1 lakh but gave up any upside above ₹50 lakh.

That ₹1 lakh is the premium. ₹50 lakh is the strike price. Three months is the expiry. Your right to buy is a call. The builder is the seller of the call, and the builder's obligation is the point of the whole contract.

A put is the same idea in reverse. It is the right to sell something at a fixed price. You would buy a put if you own something and want protection against its price falling, or if you simply expect the price to fall.

The three numbers on every option

Strike price

The strike price is the fixed price at which the option lets you buy (call) or sell (put) the underlying. For Nifty options, strikes are listed at fixed intervals, typically every 50 points, so you see 24,000, 24,050, 24,100 and so on.

A call with a strike below the current Nifty level is "in the money": the right to buy below the market has obvious value. A call with a strike above the current level is "out of the money": the right to buy above the market is only worth something if Nifty rises. Puts are the reverse.

Premium

The premium is what the buyer pays and the seller receives. It is quoted per unit, and you multiply by the lot size to get the rupee amount. The premium has two parts. Intrinsic value is how far in the money the option already is. Time value is the extra people pay for the chance that it moves further into the money before expiry. Time value shrinks every day and is zero at expiry. This shrinkage is called time decay.

Expiry

Expiry is the date the contract ends. Indian index options are cash settled: nobody delivers 75 units of Nifty, the difference between the strike and the final settlement price is paid in cash. Nifty options expire weekly and monthly. The exact day of the week has changed more than once, so check the current contract specification on the NSE website rather than trusting a video. Indian options are European style, meaning they are settled at expiry rather than exercised early, although you can sell your position at any time before that to close it.

Buyer versus seller: who owes what

This is the part beginners skip, and it is the part that decides who loses how much.

The option buyer

The buyer pays the premium up front and has a right, not a duty. The most a buyer can lose is the premium paid. That sounds safe, and it is why beginners start here. The catch is that losing the entire premium is the common outcome, not the rare one. Most out-of-the-money options expire worthless, and time decay works against the buyer every single day. A buyer needs to be right about direction, about size of move, and about timing, all at once.

The option seller

The seller receives the premium and takes on an obligation. If the buyer's option ends in the money, the seller must pay the difference. For a call seller, there is no ceiling on that difference, because there is no ceiling on how high Nifty can go. For a put seller, the loss is capped only by the underlying going to zero, which for Nifty is theoretical but for a single stock is not.

Because of this, the exchange demands margin from sellers: a deposit, usually a large fraction of the contract value, that is locked in the account and adjusted every day as the position moves. If the loss grows, the broker asks for more. If the seller cannot pay, the broker closes the position. Selling options with a small account is one of the fastest ways to lose all of it, because a single large move can produce a loss many times the premium collected.

Neither side is safe. Buyers lose small amounts often. Sellers win small amounts often and occasionally lose very large ones. The margin lesson covers what the deposit actually is.

A worked example with Nifty

Nifty is at 24,000. The lot size for Nifty options at the time of writing is 75 units, but lot sizes are set by the exchange and revised, so check the current value before you do this arithmetic for real.

You expect Nifty to rise over the next week. You buy a 24,200 call expiring next week. The premium is ₹100 per unit, so the cost is ₹100 × 75 = ₹7,500. That ₹7,500 leaves your account today. It is the most you can lose on this trade.

Three outcomes at expiry:

• Nifty settles at 24,500. The call is 300 points in the money. It is worth ₹300 × 75 = ₹22,500. You paid ₹7,500, so you are ahead by ₹15,000 before brokerage, exchange charges and taxes.
• Nifty settles at 24,250. The call is 50 points in the money, worth ₹50 × 75 = ₹3,750. You paid ₹7,500. You lost ₹3,750 even though you were right about the direction. Nifty needed to be above 24,300 (strike plus premium) just for you to break even.
• Nifty settles at 24,100. Nifty rose 100 points, you were right about direction, and the call expires worthless. You lost the full ₹7,500.

On the other side of your trade, someone sold that call. They received ₹7,500 and had margin locked that, at the time of writing, is typically well over a lakh for one Nifty lot. If Nifty had settled at 25,000 instead, the seller would owe ₹800 × 75 = ₹60,000 against a ₹7,500 credit. That asymmetry is the whole reason margin exists.

Nothing here is a suggestion to buy a Nifty call. It is arithmetic. Notice how the buyer lost money in two of three scenarios despite Nifty rising in all three.

Option trading basics India: what the rules mean for you

Options in India trade on NSE and BSE through a SEBI-registered broker. You need an activated F&O segment on your account, which requires income proof because the regulator wants to be sure you can absorb losses. That requirement is a hint about what follows.

SEBI's own studies of individual F&O traders have found that a large majority lose money. The exact figures are in SEBI's published reports and they are worth reading before you activate the segment. The lesson on why most people lose money covers the behavioural side.

META is an education provider, not a SEBI-registered investment adviser. Nothing on this page is a recommendation to trade any option. The free Trading for Everybody course covers the mechanics in Hindi, and it starts with the cash market for a reason: options make sense only after you can read a chart and size a position in plain shares. The types of trading lesson shows where options sit relative to those simpler ways to trade.

Common mistakes

• Buying far out-of-the-money options because they are cheap. A ₹5 option is cheap because it almost never pays. Price reflects probability.
• Ignoring time decay. Holding a weekly option over several quiet days burns premium even when Nifty does not move.
• Confusing direction with profit. Being right about the move is not enough. The move must beat the premium before expiry.
• Selling options "for regular income" with a small account. One large gap can wipe out months of small credits and more.
• Trading on someone's call. Options are the favourite product of tip sellers because one lucky trade makes a good screenshot. The losing trades are never posted.
• Skipping position sizing. A ₹7,500 premium is the full risk. If that is more than one percent of the account, the trade is too big. The one percent rule applies to premium exactly as it applies to a stop-loss.

Key takeaways

• A call is the right to buy at a strike; a put is the right to sell. The buyer pays a premium for the right.
• The buyer's maximum loss is the premium, and losing all of it is common.
• The seller receives the premium, carries an obligation, posts margin, and can lose many times what was collected.
• Every option has a strike, a premium and an expiry. Time value falls to zero at expiry.
• Nifty options are cash settled and lot sizes change; check the exchange's current values.
• Options are not a shortcut past learning charts and sizing. Most individual F&O traders lose money.