One of the questions students ask the most when working on a research project is "How do I know when I need to include a citation?"  The simple answer is this: if it is not your original thought, cite it.  For some examples of the gray areas, see The Magical Guide to Avoiding Plagiarism below.

Infographic created by Kate Hart, http://www.katehart.net/2012/06/citing-sources-quick-and-graphic-guide.html

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