Password: A string that an individual uses together with their user ID for authentication.

PIN (Personal Identification Number): A serial number given to an individual for their identification.

Port number: The port number used for intercommunication in TCP/UDP. Its range is from 0 to 65535.

Private authentication: An authentication method where user authentication is performed according to the combination of credentials specified by the administrator. This method takes precedence over other authentication methods.

Punch: An event that indicates the start time or the end time of work.

Punch in: The act of recording the time of arrival at the workplace.

Punch out: The act of recording the time of departure from the workplace.