From OWL at Purdue: https://owl.english.purdue.edu/owl/resource/560/13/
A literature review is a critical summary of what the scientific literature says about your specific topic or question. Often student research in APA fields falls into this category. Your professor might ask you to write this kind of paper to demonstrate your familiarity with work in the field pertinent to the research you hope to conduct.
A literature review typically contains the following sections:
Some instructors may also want you to write an abstract for a literature review, so be sure to check with them when given an assignment. Also, the length of a literature review and the required number of sources will vary based on course and instructor preferences.