According to the Encyclopedia of Research Methods, "literature reviews are systematic syntheses of previous work around a particular topic."
A literature review finds, summarizes, organizes and presents a body of knowledge on a topic. A literature review can be a stand alone document that only examines the literature on a specific subject.
A literature review might also be one section of an academic paper. This section introduces a topic and significant research in the field. A review of the literature on your topic will help frame your research and explain why it is important.
Original document, source or text without any criticism or interpretation. Includes primary research articles that report the results of original research.
An analysis, interpretation or evaluation of primary source information. Includes opinion, review, discussion or summary.