The purchase of put or call option contracts allows the trader to profit if the underlying security drops in value (puts) or increases (calls). (pocketsense.com)
If you have purchased two XYZ put options with a lot size 500, a strike price of Rs 100, and expiry month of August, you will have to buy two XYZ call options contracts with an expiry month of August. (kotaksecurities.com)
For example, a single call option contract may give a holder the right to buy 100 shares of Apple stock at a price of $ 100 until Dec. 31, 2017. (investopedia.com)