When you quote or paraphrase the idea of another person in your research paper or speech, you must provide a proper citation for the source in a bibliography or list of references. This gives credit to the author and enables the reader to locate the resource you cited.
Providing references for sources you used also lends credibility to your work, especially if you use authoritative sources.
If you use other people's ideas and do not give them credit by providing proper references to their work, you are committing plagiarism. Plagiarism is an honor code violation at NSU as well as a federal crime.