A plagiarism report is a document that provides information about the level of originality and uniqueness in a piece of written work. It checks for instances where the text has been copied from other sources without proper citation or attribution, which would constitute as plagiarizing someone else's work. The report will highlight any matching texts found online or within a database, indicating how much of the content is considered to be plagiarized. This tool helps writers and researchers ensure that their writing is original and properly cited, avoiding instances of unintentional plagiarism.