Learning how to cite may seem like a daunting task. However, it is well worth it in the end for several reasons:
- To avoid plagiarism
- To show academic honesty
- To allow others to learn more about your topic.
- To allow the reader to conduct their own research from your work
- Not "common knowledge"
Whether you choose to add a direct quotation to your paper or merely paraphrase someone else's idea, you must cite any work that did not come from you. That includes but is not limited to text, images, computer code and charts.
Remember when in doubt, cite it!
(from Florida Atlantic University, Broward College, Chicago Manual of Style Guide)