Buying & Selling Call Options
You're correct. If you have no option position at execution then you carry no risk. Your risk is only based on the net number of options you're holding at execution. This is handled by your broker or clearinghouse. Pretend that you wrote 1000 options, (you're short the call) then you bought 1000 of the same option (bought to cover) ... you are now flat and have zero options exposure. Pretend you bought 1000 options (you're long the calls) then you sold 1000 of them (liquidated your long) ... you are now flat and have zero options exposure. If you sold bought a call option then as you stated sold it to someone else what you are doing is selling the call you bought. That leaves you with no position.  This is the case if you are talking about the same strike, same expiration.
"There's no free lunch. Here are some positions that should be economically equivalent (same risk and reward) in a theoretically-pure universe with no regulations or transaction costs: You're proposing to buy the call. If you look at the equivalent, stock plus protective put, you can quickly see the ""catch""; the protective put is expensive. That same expense is embedded in the call option. See put-call parity on Wikipedia for more: http://en.wikipedia.org/wiki/Put%E2%80%93call_parity You could easily pay 10% a year or more for the protection, which could easily eat up most of your returns, if you consider that average returns on a stock index might be about 10% (nominal, not real). Another way to look at it is that buying the long call and selling a put, which is a synthetic long position in the stock, would give you the put premium. So by not selling the put, you should be worse off than owning the stock - worse than the synthetic long - by about the value of the put premium. Or yet another way to look at it is that you're repeatedly paying time value on the long call option as you roll it. In practical world instead of theory world, I think you'd probably get a noticeable hit to returns just from bid-ask and commissions, even without the cost of the protection. Options cost more. Digressing a bit, some practical complications of equivalency between different combinations of options and underlying are: Anyway, roughly speaking, any position without the ""downside risk"" is going to have an annual loss built in due to the cost of the protection. Occasionally the options market can do something weird due to supply/demand or liquidity issues but mostly the parity relationships hold, or hold closely enough that you can't profit once expenses are considered. Update: one note, I'm talking about ""vanilla"" options as traded in the US here, I guess there are some somewhat different products elsewhere; I'm not sure exactly which derivatives you mean. All derivatives have a cost though or nobody would take the other side of the trade." "fennec has a very good answer but i feel it provides too much information. So i'll just try to explain what that sentence says. Put option is the right to sell a stock. ""16 puts on Cisco at 71 cents"", means John comes to Jim and says, i'll give you 71 cent now, if you allow me to sell one share of Cisco to you at $16 at some point in the future ( on expiration date).  NYT quote says 1000 puts that means 1000 contracts - he bought a right to sell 100,000 shares of Cisco on some day at $16/share. Call option - same idea: right to buy a stock." The value of an option has 2 components, the extrinsic or time value element and the intrinsic value from the difference in the strike price and the underlying asset price. With either an American or European option the intrinsic value of a call option can be 'locked in' any time by selling the same amount of the underlying asset (whether that be a stock, a future etc).  Further, the time value of any option can be monitised by delta hedging the option, i.e. buying or selling an amount of the underlying asset weighted by the measure of certainty (delta) of the option being in the money at expiry. Instead, the extra value of the American option comes from the financial benefit of being able to realise the value of the underlying asset early. For a dividend paying stock this will predominantly be the dividend. But for non-dividend paying stocks or futures, the buyer of an in-the-money option can realise their intrinsic gains on the option early and earn interest on the profits today. But what they sacrifice is the timevalue of the option.  However when an option becomes very in the money and the delta approaches 1 or -1, the discounting of the intrinsic value (i.e. the extra amount a future cash flow is worth each day as we draw closer to payment) becomes larger than the 'theta' or time value decay of the option. Then it becomes optimal to early exercise, abandon the optionality and realise the monetary gains upfront. For a non-dividend paying stock, the value of the American call option is actually the same as the European. The spot price of the stock will be lower than the forward price at expiry discounted by the risk free rate (or your cost of funding). This will exactly offset the monetary gain by exercising early and banking the proceeds. However for an option on a future, the value today of the underlying asset (the future) is the same as at expiry and its possible to fully realise the interest earned on the money received today. Hence the American call option is worth more. For both examples the American put option is worth more, slightly more so for the stock. As the stock's spot price is lower than the forward price, the owner of the put option realises a higher (undiscounted) intrinsic profit from selling the stock at the higher strike price today than waiting till expiry, as well as realising the interest earned. Liquidity may influence the perceived value of being able to exercise early but its not a tangible factor that is added to the commonly used maths of the option valuation, and isn't really a consideration for most of the assets that have tradeable option markets. It's also important to remember at any point in the life of the option, you don't know the future price path. You're only modelling the distribution of probable outcomes. What subsequently happens after you early exercise an American option no longer has any bearing on its value; this is now zero! Whether the stock subsequently crashes in price is irrelevent. What is relevant is that when you early exercise a call you 'give up' all potential upside protected by the limit to your downside from the strike price. "You may look into covered calls.  In short, selling the option instead of buying it ... playing the house.   One can do this on the ""buying side"" too, e.g. let's say you like company XYZ.  If you sell the put, and it goes up, you make money.  If XYZ goes down by expiration, you still made the money on the put, and now own the stock - the one you like, at a lower price.  Now, you can immediately sell calls on XYZ.  If it doesn't go up, you make money.  If it does goes up, you get called out, and you make even more money (probably selling the call a little above current price, or where it was ""put"" to you at). The greatest risk is very large declines, and so one needs to do some research on the company to see if they are decent -- e.g. have good earnings, not over-valued P/E, etc.  For larger declines, one has to sell the call further out.  Note there are now stocks that have weekly options as well as monthly options.  You just have to calculate the rate of return you will get, realizing that underneath the first put, you need enough money available should the stock be ""put"" to you.   An additional, associated strategy, is starting by selling the put at a higher than current market limit price.  Then, over a couple days, generally lowering the limit, if it isn't reached in the stock's fluctuation.  I.e. if the stock drops in the next few days, you might sell the put on a dip.   Same deal if the stock finally is ""put"" to you.  Then you can start by selling the call at a higher limit price, gradually bringing it down if you aren't successful -- i.e. the stock doesn't reach it on an upswing. My friend is highly successful with this strategy. Good luck" "When you enter into a multi-legged trade where one is a buy and one is a sell, the limit is expressed as either: The gist is that you don't care what each individual piece costs; you only care what the cost of the bundle is. When you put on a buy-write, you are buying stock and selling a (covered) call against that stock.  That trade will always cost money. Putting on a buy-write will always be done at a net debit.  This is because is is normally impossible for a call to be worth more than its underlying stock price.  There are a few possible reasons there would be a""net credit"" option for what's described as a ""buy-write"":" I wouldn't choose any of the above. Buying stocks and staying long in my case is the cheapest way to go (retail brokerage commissions have just been getting cheaper and cheaper. )   The added costs of trading options make it even dicier for me, a retail investor, to take risks. To understand how to make money with options, I'd have to be much more sophisticated investor. I would make a change to the answer from olchauvin: If you buy a call, that's because you expect that the value of call options will go up. So if you still think that options prices will go up, then a sell-off in the stock may be a good point to buy more calls for cheaper. It would be your call at that point (no pun intended). Here is some theory which may help. An options trader in a bank would say that the value of a call option can go up for two reasons: The VIX index is a measure of the levels of implied volatility, so you could intuitively say that when you trade options you are taking a view on two components: the underlying stock, and the level of the VIX index. Importantly, as you get closer to the expiry date this second effect diminishes: big jumps up in the VIX will produce smaller increases in the value of the call option. Taking this point to its limit, at maturity the value of the call option is only dependent on the price of the underlying stock. An options trader would say that the vega of a call option decreases as it gets closer to expiry. A consequence of this is that if pure options traders are naturally less inclined to buy and hold to expiry (because otherwise they would really just be taking a view on the stock price rather than the stock price & the implied volatility surface). Trading options without thinking too much about implied volatities is of course a valid strategy -- maybe you just use them because you will automatically have a mechanism which limits losses on your positions. But I am just trying to give you an impression of the bigger picture. Try wallstreetsurvivor.com It gives you $100k of pretend money when you sign up, using which you can take various courses on the website. It will teach you how to buy/sell stocks and build your portfolio. I am not sure if they do have Options Trading specifically, but their course line up is great!