Style guides, like the MLA and APA, explain how you should format your written work and how you should cite your references.
Citations are important because they:
What sources need to be cited?
Any time you quote or paraphrase the ideas of another, you should provide a citation.
You do not need to cite things which are common knowledge ("there are seven days in a week" or "the sky is blue") or your own opinion, but you DO need to provide citations for the facts and opinions you borrow from others.
Ever get confused by citation jargon? Know what MLA format stands for? Need help understanding the differences between a primary source and a secondary source? Our list of terms and definitions below can help!