When you use information or ideas created by other people in your essays or assignments, you need to let readers know you have done this.
Copying something written by another person and putting it into your assignment as if it is your own work is known as PLAGIARISM. You are not allowed to do this in college.
There are two basic types of referencing system:
Author Date This is also known as the Harvard Referencing System
Numbered Notes Such as The British Journal of Nutrition style