Acceptance is the unqualified agreement to the terms of an offer. An offer is a proposal from one party to another intending to create a legal obligation upon acceptance.Offer and acceptance in formation of contract. 2207. The general rule is that a contract is effective when both parties agree (ie, sign the Agreement of Sale) AND acceptance is communicated to the offering party. An offer is a clear intention to enter into a legally binding agreement. It marks the first step in creating that agreement. This video defines "contract" and "consideration" in terms anyone can understand.