It's important to cite sources you used in your research for several reasons.
Citing a source means that you show, within the body of your text, that you took words, ideas, figures, images, etc. from another place.
Citations are a short way to uniquely identify a published work (e.g. book, article, chapter, web site). They are found in bibliographies and reference lists and are also collected in article and book databases.
Citations consist of standard elements, and contain all the information necessary to identify and track down publications, including:
Academic organizations and some disciplines outline their own styles of how to cite sources and format research papers. You may have heard of or used some of the styles when writing your paper.