The Strike Price is the exact price that a trader agrees on to buy or sell the underlying asset. The Strike Price is also called Exercise Price.
If the trader is the owner of the option contract, i.e., is in a long position, the strike price refers to the price at which the trader has the right to buy (in case of a long call) or sell (in case of a long put) the underlying asset.
Conversely, if the trader is the seller of the option contract, i.e., is in a short position, the strike price refers to the price at which the trader has the obligation to buy (in case of a short put) or sell (in case of a short call) the underlying asset.
Example
