Citing is more than just creating a Reference or Works Cited List!
Whenever you use another person's language, ideas, or other original content, you need to acknowledge this both within the body of your paper using in-text citations and at the end of your paper in the bibliography or reference page.
Your professor will let you know what citation style guide (e.g., APA, MLA) is required for the assignment. This style guides are usually specific to your discipline or area of study.
APA (American Psychological Association) - commonly used in the Social Sciences.
MLA (Modern Language Association) - commonly used for Humanities and Liberal Arts.