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$MachineDomain$UserName

$MachineID

FilledSmallSquare$MachineID is a string which gives, if possible, a unique identification code for the computer on which Mathematica is being run.

FilledSmallSquare On many computers, $MachineID is the MathID string printed by the external program mathinfo.

FilledSmallSquare See The Mathematica Book: Section 2.13.5.

FilledSmallSquare See also: $SystemID, $MachineName.

$MachineDomain$UserName