What Is a Stock Option?
A stock option (also known as an equity option), gives an investor the right, but not the obligation, to buy or sell a stock at an agreed-upon price and date. There are two types of options: puts, which is a bet that a stock will fall, or calls, which is a bet that a stock will rise.
Because it has shares of stock (or a stock index) as its underlying asset, stock options are a form of equity derivative and may be called equity options.
Employee stock options (ESOs) are a type of equity compensation given by companies to some employees or executives that effectively amount to call options. These differ from listed equity options on stocks that trade in the market, as they are restricted to a particular corporation issuing them to their own employees.