Plagiarism is the act of stealing/copying another person’s work without giving reference to the original piece or author. Plagiarism as an act is considered an offence in academic writing as it is seen as passing off someone else’s writing as the perpetrator of the act’s own original thoughts and is seen as lazy, theft and as nothing have been learnt from what been taught. Plagiarism could lead to different penalties for certain people, like when student plagiarizes, they might kicked off a course or a worker getting fired.
In the art world, plagiarism is used through different means. Plagiarism in art is done through tracing / recreating parts or an entirety of a piece or taking reference in a non subtle way (redrawing entire elements of another pieces while only changing a few things about the piece) without properly giving credit to the original creator, with no form of homage within the creation of the piece. One of the most famous cases of plagiarism is by Roy Lichtenstein, whose art is all derived from sources like contemporary comic books.