A literature review summarizes and synthesizes the existing scholarly research on a particular topic. It is not an annotated bibliography or research paper. It is most often used when writing theses, dissertations, and capstone projects. It establishes what is already known about a topic by reviewing the scholarly work currently available (aka "the literature"). It may also identify a research question that "the literature" doesn't answer; pointing to a potential research opportunity.
Conducting Research Literature Reviews by 
Preparing Literature Reviews-3rd Ed by 
Doing a Literature Review in Health and Social Care by 
The Student's Guide to Preparing Dissertations and Theses by 
