Colors play an important role in our impressions. For example, Colson Whitehead points out that red and gold are associated with royalty and luxury. Because no one can remember all the specific rules of citation, it is a good idea to purchase one of the many handbooks or style manuals available. Check with your instructor or the Writing Center for suggestions. Most fields are grounded in a body of common knowledge shared by scholars in the field.
Examples are historical dates and established scientific principles.
You do not need to cite facts or ideas that are common knowledge in the field you are studying, as long as you express them in your own sentences. When you can not be sure what is common knowledge and what is not, play it safe and cite your sources. You are more likely to risk plagiarizing when you Do not understand the material well enough to be able to use it. Rely too heavily on the ideas of others or presume their ideas are preferable to your own. Do not know the correct methods of citation and attribution.