A call option, usually just labeled a "call", is simply a money agreement i.e. a contract, between 2 people, a buyer and the seller . The buyer of the call has the 'right', but is not required, to buy an agreed upon amount of a financial entity, such as a stock, from the seller at a predetermined point in time (called option expiration date) for an agreed upon price (called the strike price). Visit the site for more info.

what is an option call