  Information processing at the molecular scale is limited by thermal
fluctuations. This can cause undesired consequences in copying information
since thermal noise can lead to errors that can compromise the functionality of
the copy. For example, a high error rate during DNA duplication can lead to
cell death. Given the importance of accurate copying at the molecular scale, it
is fundamental to understand its thermodynamic features. In this paper, we
derive a universal expression for the copy error as a function of entropy
production and {\cred work dissipated by the system during wrong
incorporations}. Its derivation is based on the second law of thermodynamics,
hence its validity is independent of the details of the molecular machinery, be
it any polymerase or artificial copying device. Using this expression, we find
that information can be copied in three different regimes. In two of them, work
is dissipated to either increase or decrease the error. In the third regime,
the protocol extracts work while correcting errors, reminiscent of a Maxwell
demon. As a case study, we apply our framework to study a copy protocol
assisted by kinetic proofreading, and show that it can operate in any of these
three regimes. We finally show that, for any effective proofreading scheme,
error reduction is limited by the chemical driving of the proofreading
reaction.
