An option is a type of financial instrument that's tied to an underlying security. Options give their buyers the right, but not the obligation, to purchase or sell the asset at a specified...
In finance, an option is a contract which conveys to its owner, the holder, the right, but not the obligation, to buy or sell a specific quantity of an underlying asset or instrument at a specified strike price on or before a specified date, depending on the style of the option.
Buying an option is simply purchasing a contract that represents the right, but not the obligation, to buy or sell a security at a fixed price by a specified date.