'A literature review is an account of what has been published on a topic by accredited scholars and researchers. Occasionally you will be asked to write one as a separate assignment ...., but more often it is part of the introduction to an essay, research report, or thesis. In writing the literature review, your purpose is to convey to your reader what knowledge and ideas have been established on a topic, and what their strengths and weaknesses are. As a piece of writing, the literature review must be defined by a guiding concept (e.g., your research objective, the problem or issue you are discussing, or your argumentative thesis). It is not just a descriptive list of the material available, or a set of summaries.'

(Dena Taylor, Health Sciences Writing Centre, University of Toronto).  http://advice.writing.utoronto.ca/types-of-writing/literature-review/

This page on Writing a Literature Review from Queensland University of Technology - from why we need to write literature reviews to what to consider when analyzing the literature and the writing and structuring of a literature review -  is a good starting point and overview of the process.

You may find some of these other guides useful on other aspects of the literature review process:

What is a literature review?   (RMIT University, Melbourne - Learning Lab).                                                                                                                           

The Literature Review: A Few Tips On Conducting It   (University of Toronto - Writing Advice).                                                                                      

This web guide from Central Queensland University Library provides a more in-depth guide to the process of the literature review: from selecting your topic and putting it in context, to looking at and using information sources and organising information; and finally the positioning of  the literature review and writing the literature review.