When buying a call option, the strike price of an option for a stock, for example, will be determined based on the current price of that stock. For example, if a share of a given stock (like Amazon (AMZN) ) is $1,748, any strike price (price of the call option) that is above that share price is considered to be "out of the money." Conversely, if the strike price is under the current share price of the stock, it's considered "in the money." 
Options belong to the larger group of securities known as derivatives. A derivative's price is dependent on or derived from the price of something else. As an example, wine is a derivative of grapes ketchup is a derivative of tomatoes, and a stock option is a derivative of a stock. Options are derivatives of financial securities—their value depends on the price of some other asset. Examples of derivatives include calls, puts, futures, forwards, swaps, and mortgage-backed securities, among others.

Covered calls can make you money when the stock price increases or stays pretty constant over the time of the option contract. However, you could lose money with this kind of trade if the stock price falls too much (but can actually still make money if it only falls a little bit). But by using this strategy, you are actually protecting your investment from decreases in share price while giving yourself the opportunity to make money while the stock price is flat. 

The purchase of a call option is a long position, a bet that the underlying futures price will move higher. For example, if one expects corn futures to move higher, they might buy a corn call option. The purchase of a put option is a short position, a bet that the underlying futures price will move lower. For example, if one expects soybean futures to move lower, they might buy a soybean put option.
All investors should know how to trade options and have a portion of their portfolio set aside for option trades. Not only do options provide great opportunities for leveraged plays; they can also help you earn larger profits with a smaller amount of cash outlay. What’s more, option strategies can help you hedge your portfolio and limit potential downside risk.
Trading in commodity futures contracts can be very risky for the inexperienced. The high degree of leverage used with commodity futures can amplify gains, but losses can be amplified as well. If a futures contract position is losing money, the broker can initiate a margin call, which is a demand for additional funds to shore up the account. Further, the broker will usually have to approve an account to trade on margins before they can enter into contracts.
* Sell orders are subject to an activity assessment fee (from $0.01 to $0.03 per $1,000 of principal). Trades are limited to online domestic equities and options and must be used within two years. Options trades are limited to 20 contracts per trade. Offer valid for new and existing Fidelity customers opening or adding net new assets to an eligible Fidelity IRA or brokerage account. Deposits of $50,000-$99,999 will receive 300 free trades, and deposits of $100,000 or more will receive 500 free trades. Account balance of $50,000 of net new assets must be maintained for at least nine months; otherwise, normal commission schedule rates may be retroactively applied to any free trade executions. See Fidelity.com/ATP500free for further details and full offer terms. Fidelity reserves the right to modify these terms and conditions or terminate this offer at any time. Other terms and conditions, or eligibility criteria may apply.
Unlike other investments where the risks may have no boundaries, options trading offers a defined risk to buyers. An option buyer absolutely cannot lose more than the price of the option, the premium. Because the right to buy or sell the underlying security at a specific price expires on a given date, the option will expire worthless if the conditions for profitable exercise or sale of the option contract are not met by the expiration date. An uncovered option seller (sometimes referred to as the uncovered writer of an option), on the other hand, may face unlimited risk.
Remember, a stock option contract is the option to buy 100 shares; that’s why you must multiply the contract by 100 to get the total price. The strike price of INR 300 means that the stock price must rise above INR 300 before the call option is worth anything; furthermore, because the contract is INR 10 per share, the break-even price would be INR 310(INR 300 + INR 10).
The less time there is until expiry, the less value an option will have. This is because the chances of a price move in the underlying stock diminish as we draw closer to expiry. This is why an option is a wasting asset. If you buy a one-month option that is out of the money, and the stock doesn’t move, the option becomes less valuable with each passing day. Since time is a component to the price of an option, a one-month option is going to be less valuable than a three-month option. This is because with more time available, the probability of a price move in your favor increases, and vice versa.
Options are powerful because they can enhance an individual’s portfolio. They do this through added income, protection, and even leverage. Depending on the situation, there is usually an option scenario appropriate for an investor’s goal. A popular example would be using options as an effective hedge against a declining stock market to limit downside losses. Options can also be used to generate recurring income. Additionally, they are often used for speculative purposes such as wagering on the direction of a stock.
What if, instead of a home, your asset was a stock or index investment? Similarly, if an investor wants insurance on his/her S&P 500 index portfolio, they can purchase put options. An investor may fear that a bear market is near and may be unwilling to lose more than 10% of their long position in the S&P 500 index. If the S&P 500 is currently trading at $2500, he/she can purchase a put option giving the right to sell the index at $2250, for example, at any point in the next two years.

The currency market, or foreign exchange market ("forex"), was created to facilitate the exchange of currency that becomes necessary as the result of foreign trade. That is, when an entity in one country sells something to an entity in another country, the seller earns that foreign currency. When China sells t-shirts to Walmart, for example, China earns US dollars. When Toyota wants to build a factory in the US, it needs dollars. It may get those from its local bank, which in turn will obtain them in the international currency market. This market exists to facilitate these types of exchanges.

Volatility: If an options market is highly volatile (i.e. if its daily price range is large), the premium will be higher, because the option has the potential to make more profit for the buyer. Conversely, if an options market is not volatile (i.e. if its daily price range is small), the premium will be lower. An options market's volatility is calculated using its long-term price range, its recent price range, and its expected price range before its expiration date, using various volatility pricing models.
According to Nasdaq's options trading tips, options are often more resilient to changes (and downturns) in market prices, can help increase income on current and future investments, can often get you better deals on a variety of equities and, perhaps most importantly, can help you capitalize on that equity rising or dropping over time without having to invest in it directly.