The System Tags folder contains predefined tags that have specific functions (time, date, acknowledge alarms, storage of the logged user, and so forth). You cannot edit or delete these tags; but you can access their values from any IWS task, copy them, and use them elsewhere.
For a list of system tags, including their properties and descriptions, see List of System Tags.
You can view the properties of a system tag using the System Tags datasheet, which contains four columns (Name, Size, Type, and Description).