sentences:  For example, an access control list could be used for granting or denying write access to a particular system file, but it would not dictate how that file could be changed.In an RBAC-based system, an operation might be to 'create a credit account' transaction in a financial application or to 'populate a blood sugar level test' record in a medical application.The assignment of permission to perform a particular operation is meaningful, because the operations are granular with meaning within the application.