Plagiarism is presenting someone else's work as your own. Even if you have permission from the owner, it is still plagiarism to use their work as your own without citing the source. There are four types of plagiarism: direct, mosaic, self, and accidental. Direct means you intentionally use someone else's content as your own with no acknowledgement. Mosaic: using some of someone else's content, but not quoting the owner properly. Self: using your previous work for a present assignment. Accidental: unintentional using someone else's work without acknowledgement.