Wikipedia:Plagiarism

Plagiarism is taking credit for someone else's writing as your own, including their language and ideas, without providing adequate credit. The University of Cambridge defines plagiarism as: "submitting as one's own work, irrespective of intent to deceive, that which derives in part or in its entirety from the work of others without due acknowledgement."

Sources are annotated using inline citations, typically in the form of footnote (see Citing sources). In addition to an inline citation, in-text attribution is usually required when quoting or closely paraphrasing source material (for example: "John Smith wrote that the building looked spectacular," or "According to Smith (2012) ..."). The Manual of Style requires in-text attribution when quoting a full sentence or more. Naming the author in the text allows the reader to see that it relies heavily on someone else's ideas, without having to search in the footnote. You can avoid inadvertent plagiarism by remembering these rules of thumb:

Plagiarism is presenting someone else's work – including their language and ideas – as your own, whether intentionally or inadvertently. Because it can happen easily and by mistake, all editors are strongly advised to actively identify any potential issues in their writing. Plagiarism can take several forms.

Be cautious when using in-text attribution, because it can lead to other problems. For example, "According to Professor Susan Jones, human-caused increases in atmospheric carbon dioxide have led to global warming" might be a violation of NPOV, because this is the consensus of many scientists, not only a claim by Jones. In such cases, plagiarism can be avoided by summarizing information in your own words or acknowledging explicitly that while the words are from Jones, the view is widespread.

You can avoid plagiarism by summarizing source material in your own words followed by an inline citation, or by quoting or closely paraphrasing the source, usually with in-text attribution (adding the author's name to the text) and an inline citation. The following examples are adapted from "What Constitutes Plagiarism?", Harvard Guide to Using Sources, Harvard University:

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