Most academic writing requires you to acknowledge the source of the ideas and information you use in your assignments. You will need to acknowledge sources in the actual body of your assignment (in-text citations) and you need to provide full details of all sources in a properly formatted reference list or bibliography at the end of your assignment (referencing).
Information about referencing can be found in
the Faculty Current Students page or the Student Resources page under each of the Schools
Different disciplines (e.g. business, law, psychology) use different styles. You cannot mix styles.
This often means you need to learn several different styles of referencing through your university course