This page includes material from our excellent Literature Reviews research guide.
See that guide for much more information about writing lit reviews.
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:
"Literature Reviews: An Overview for Graduate Students" by North Carolina State University Libraries.