Plagiarism is the use of someone else's work, either copied or paraphrased, which you pass off as your own by failing to cite its true source. Any phrases and sentences taken from any other work (including any other student essay) must be set out as a quotation by being enclosed in inverted commas. The work from which it is taken must be acknowledged in a footnote. When you need to set out the argument of an authority (which should not happen often), paraphrasing is preferable to quotation at length. In either case, the authority must be properly cited. It is usual also to mention the name of the authority in the text, often with an indication of why you consider it important.
Please note: Students should be aware that plagiarism, particularly from the web, is usually easily detected by academic staff and the consequences for students are severe.
Plagiarism in any form is unethical and unacceptable. A paper of which any portion is plagiarised may well be failed and even receive no mark at all. This also applies to unauthorised collaboration between students and essays you have already submitted for another subject.
For more information please see the University Student Academic Integrity Policy (MPF1310).