A literature review is a systematic survey of the scholarly literature published on a given topic. Rather than providing a new research insight, a literature review lays the groundwork for an in-depth research project analyzing previous research. Type of documents surveyed will vary depending on the field, but can include:
A thorough literature review will also require surveying what librarians call "conference papers," which includes difficult-to-locate documents such as:
Why we do them!
Purpose of the Literature Review
The purpose of the literature review remains the same regardless of the research method you use. It tests your research question against what already is known about your subject. So your review will
Determine the limits or boundaries of the research problem
Identify studies, models, case studies, etc., supporting your topic