Financial contracts known as call options grant the option buyer the right, but not the duty, to purchase a stock, bond, commodity, or other asset or instrument at a particular price within a predetermined window of time. The underlying asset is a stock, bond, or product. When the value of the underlying asset rises, the call buyer makes money. A put option, as contrast to a call option, allows the holder to sell the underlying asset at a predetermined price on or before the expiration date.
