That's not YOUR song! It's mine!
What is Plagiarism?
Plagiarism is the copy, use, and publication of one's work said to be another's. Plagiarism often goes with Piracy and Copyright Infringement.
Why is Plagiarism a Problem?
Plagiarism is a problem because if the one who makes the song, book, essay, movie, video, or idea has another claiming the fame they won't get credit. When this happens, the credibility of both persons can be demolished.