stock options
For our purposes, we will identify two broad categories of stock options: stock market options (often simply called stock options) and employee stock options (also often simply called stock options). Stock market stock options are financial instruments generally traded on a stock or stock option exchange. These options give the owner the right, but not the obligation, to buy or sell a given asset (in this case shares of a company's stock) at a fixed price on or before an expiration date.
Employee Stock Options are subset of this broad category where the given asset (or underlying asset) is the stock of the company at which the employee is employed.
video