The assignment is not the obvious mode of discharge of a contract.All agreements are not contract. Only those agreements which are enforceable by law are contracts. Following are the essential requirements of a valid contract.Offer and its acceptance 'Free consent of both partiesMutual and lawful consideration for agreement It should be enforceable by law. Hence, the intention should be to create a legal relationship. Agreements of social or domestic nature are not contractsParties should be competent to contractAn object should be lawfulCertainty and possibility of performanceThe contract should not have been declared as void under the Contract Act or any other law A contract can be discharged by performance, Mutual agreement, Impossibility of performance, Lapse of time, breach of contract, remission or due to merger of rights.A contract may be deemed void should the terms require one or both parties to participate in an illegal act, or if a party becomes incapable of meeting the terms.Alternatively, a contract is voidable when one or both parties were not legally capable of entering into the agreement, such as when one party is a minor.