Abstract: A password formed of several fields (101-105) is presentable in a series of instances (100, 110, 120, 130). The fields include at least one of (a) a static field (105) that does not change upon each instance of the password and (b) a dynamic field (101, 102) that changes with each instance of the password based upon extrinsic data. Further, there is a “hysteresis” field (or a “dynamic field with history”, 103, 104) which contains data that is a function of a preceding instance of the password. When a current presented instance (110) of the password is input/received, a comparison operation is performed in which the hysteresis field (113, 114) of the current presented instance of the password is compared using data retained since a prior instance of authentication of the password (101, 102).