Options contracts are agreements between a buyer and seller which give the buyer the right to buy or sell a particular asset at a later date (expiration date) and an agreed-upon price (strike price).  They’re often used for securities, commodities, and real estate transactions.In other words, buyers can purchase them much like other types of assets within brokerage accounts.  What Are Call & Put Options?
An underlying security is an asset that a derivative instrument (e.g.futures, options) derives its value from.