In all types of research writing, it is necessary to document the source works that underpin particular concepts, positions, propositions and arguments with citations. The bibliographic citations you include in your papers serve a number of purposes:
Provide evidence that your position is well-researched and
The references you provide your readers allow you to demonstrate that your position or argument is thoroughly researched and that you have referenced, or addressed, the critical authorities relevant to the issues. Researching what others have written about your topic allows you to support your own position with the opinions of experts, shows that you are able to address the opinions of those who might disagree with you, and generally illustrates that you have educated yourself by consulting experts in the field.
Give credit to the author of an original concept or theory presented.
Giving proper attribution to those whose thoughts, words, and ideas you use is an important concept in scholarly writing. For these reasons, it is important to adopt habits of collecting the bibliographic information on source works necessary for correct citations in an organized and thorough manner.
Understanding and adhering to the guidelines for attributing concepts and ideas to others, too, is an important part of the research
Help readers identify and locate the source work.
Readers often want to locate a work you have cited, either to verify the information, or to learn more about issues and topics addressed by the work. It is important that readers should be able to find the works you have used to inform your research easily and efficiently from the information included in your citations (see the "Citation Structure" topic on the following page for details).
This is where styles like "APA," MLA, Chicago, CBE, and others come in: they provide researchers and readers with a system of signals that let us know what type of work you are citing, and, thus, where we might go about locating the work if we want to read it ourselves.