Warez refers primarily to copyrighted works distributed without fees or royalties, and may be traded, in general violation of copyright law. The term generally refers to unauthorized releases by organized groups, as opposed to file sharing between friends or large groups of people with similar interest using a darknet. It usually does not refer to commercial software counterfeiting. This term was initially coined by members of the various computer underground circles, but has since become commonplace among Internet users and the mass media.
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http://en.wikipedia.org/wiki/Warez