A contract is an agreement having a lawful object entered into voluntarily by two or more parties, each of whom intends to create one or more legal obligations between or among them. The elements of a contract are “offer” and “acceptance” by “competent persons” having legal capacity who exchange “consideration” to create “mutuality of obligation. ” Proof of some or all of these elements may be done in writing, though contracts may be made entirely orally or by conduct.