The performance of the accord, called a satisfaction , discharges the original debt. Although an accord and satisfaction can operate without a check, generally it does involve a check. The accord is a contract to pay a stated amount to discharge a prior obligation. When either the existence or the amount of the drawer's duty under the original contract is in dispute, the drawer's promise to pay a stated amount, is consideratoin for the payee's promise to take the stated amount as full payment. With this acceptance of the offer, an accord contract is created.
Satisfaction is the payee's exercising dominion over the check by cashing or depositing it.
Upon satisfaction, the original contract duty to pay is discharged. If neither the existence nor the amount of the drawer's obligation is in dispute, the drawer has a pre-existing duty to pay the undisputed higher amount. An attempt to promise to pay only a part of the undisputed amount cannot be a promise in the contractual sense. Thus, the death or illness of a person who contracted to render personal services is a discharge of his contractual duty, or if the subject matter of the contract is destroyed. The statute of limitations doesn't exactly discharge the obligation but it may bar the other party's right to bring an action.