This post compares plagiarism and copyright infringement. It is prompted by a Quora question that I answered several months ago. (See Have your ideas or works ever been plagiarized? What happened?)
Plagiarism is the wrongful appropriate on another’s work and presenting it as one’s own. One typically thinks of plagiarism occurring in academia or journalism. However, as discussed below, it can occur in other professions, too.
Copyright Infringement Defined
The holder of the copyright in a work has certain exclusive rights with respect to that work. These include (as applicable) the rights to reproduce, distribute, publicly perform, publicly display, and make derivative works of the work. Copyright infringement is use of a work, without permission of the copyright holder, that infringes on one of those exclusive rights.