Authentication is often considered the first step of interaction with a system. However, authentication is preceded by identification. A subject can claim an identity by process of identification, thereby initiating accountability. For initiating the process of authentication, authorization, and accountability (AAA), a subject must provide an identity to a system. Typing in a password, swiping an RFID access card, or giving a finger impression, are some of the most common and simple ways of providing individual identity. In the absence of an identity, a system has no way to correlate an authentication factor with the subject. Upon establishing the identity of a subject, thereafter all actions performed would be accounted against the subject, including information-system tracks activity based on identity, and not by the individuals. A computer isn't capable of differentiating between humans. However, a computer can well distinguish between user accounts. It clearly understands that one user account is different from all other user accounts. However, simply claiming an identity does not implicitly imply access or authority. The subject must first prove its identity in order to get access to controlled resources. This process is known as identification.