An option is described by its symbol (call letters), whether its a put or a call, an expiration month and a strike price.

A Call option is a bullish contract, giving the buyer the right to buy the underlying security at a certain price by a certain date.

A Put option is a bearish contract, giving the buyer the right to sell the underlying security at a certain price by a certain date.

An expiration month is the month of which the third Friday is the date that the option contract expires.

A strike price is the price that the buyer can either buy (call) or sell (put) the underlying security by the expiration date.

Both Calls and Puts can be both bought and sold in the open market.