A literature review does not present an original argument, but instead is an overview or discussion of existing literature (scholarly writing) on a particular topic. The literature may come from books, articles, reports, or other formats.
It's a review because it usually contains a summary, synthesis, or analysis of the central arguments in the existing literature.
...an annotated bibliography.
...a research paper, although it is often part of one.
This video by NC State Libraries is an excellent explanation (not just for grad students!)
"Literature Reviews: An Overview for Graduate Students" by North Carolina State University Libraries.
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