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.
Commodity futures used by companies give a hedge to the risk of adverse price movements. The goal of hedging is to prevent losses from potentially unfavorable price changes rather than to speculate. Many companies that hedge use or producing the underlying asset of a futures contract. Examples of commodities hedging use include farmers, oil producers, livestock breeders, manufacturers, and many others.
For example: A trader in October 2016 agrees to deliver 10 tons of steel for INR 30,000 per ton in January 2017 which is currently trading at INR 29,000 per ton.  In this case, trade is assured because he got a buyer at an acceptable price and a buyer because knowing the cost of steel in advance reduces uncertainty in planning. In this case, if the actual price in January 2017 is INR 35,000 per ton, the buyer would be benefitted by INR 5,000 (INR 35000-INR 30,000). On the other hand, if the price of steel becomes INR 26,000 per ton then the trader would be benefitted by INR 4,000 (INR 30,000- INR 26000)
An option is a contract that allows (but doesn't require) an investor to buy or sell an underlying instrument like a security, ETF or even index at a predetermined price over a certain period of time. Buying and selling options is done on the options market, which trades contracts based on securities. Buying an option that allows you to buy shares at a later time is called a "call option," whereas buying an option that allows you to sell shares at a later time is called a "put option."