A literature review is a critical summary of what the scientific literature says about a 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.
When asked to do a literature review, you may find yourself wondering what "the literature" is that you need to find.
The literature is a collection of all the scholarly writings on a topic, including scholarly articles, books, and other works. This may seem like a mountain of information to work through, but in almost every field of research the literature can be seen as a series of conversations between scholars - and you don't need to be involved in every conversation to complete your review.
There are usually major works that were first written on a topic - these are authors you see cited over and over again. Then other, later works that tend to be building on or responding to the major works in some way. Basically the literature is a continuously evolving network of scholarly works that interact with each other. As you do your own research, you will begin to understand the relationships between these works and how your own ideas relate within the network.
A brief overview of some types of scholarly literature you may find in the library databases.
Empirical articles are original research articles. This type of article will have a methodology section that tells how the experiment/study was set up and conducted, a results or discussion sections, and a conclusion.
These articles are often referred to as primary research.
These articles are written to contribute to the theoretical foundations of a field of study. An author will draw upon existing research to form a new theory or explore theories in new ways.
A literature review or systematic review is written to bring together and summarize the results or conclusions from multiple empirical or theoretical articles.
This type of article will generally have a very extensive bibliography which can help you locate important authors and articles for your own research.
The general name for informally published scholarly work. These works can often be found on the internet and in specialized resources like institutional repositories or Google Scholar. They are not often not formally peer-reviewed but are especially important in the sciences.