What is a strike price?
It is the fixed price at which owner (buyer) of the CALL option can buy the underlying asset from option seller, no matter whatever is the current price of the underlying asset. Example, If strike price of Reliance CALL option is 1300 that means buyer of this option can buy Reliance stock at 1300 even if the current market price of the stock is higher (say 1500). In case of Put options, strike price is the price at which owner (buyer) of the PUT option can sell the underlying asset to the option seller, no matter whatever is the current price of the underlying asset. Example, if strike price of Reliance PUT option is 1300 that means buyer of this option can sell Reliance stock at 1300 even if the current market price of the stock is lower (say 1100).