Short for
Copy Guard Management System, CGMS is a method of
copy protection used to
prevent unauthorized
disc copying. The Copy Guard Management System first
determines if
data recorded on a recording medium is original or copied, and
then prevents the data from being copied when it is not original. A copy of the
original can be made only once, but a copy of data (secondary copy) cannot be
copied again. May also be called
Single Copy Management System (SCMS).