One of the essential elements of a contract is an agreement. An agreement shows that the parties have bound themselves to act or refrain from acting in a manner specified by the contract. It is essential to a contract that there be an offer and, while the offer is still in existence, it must be accepted without qualification. An offer expresses the willingness of the offeror to enter into a contract agreement regarding a particular subject. A contract is based upon an agreement. An agreement arises when one person, the offeror, makes an offer and the person to whom is made, the offeree, accepts. There must be both an offer and an acceptance. If either is not present, there is no contract. An offeror may make an offer to a particular person or it may be made to the public at large (for example, a reward offered to the public for return of lost property).