The Harvard referencing system is known as the Author-Date style. It emphasizes the name of the creator of a piece of information and the date of publication, with the list of references in alphabetical order at the end of your paper.
Unlike other citation styles, there is no single, definitive version of Harvard Style. Therefore, you may see a variation in features such as punctuation, capitalization, abbreviations, and the use of italics.
Always check with your instructor and follow the rules he or she gives you.