There is no point searching for references, reading books and articles, and taking notes if you can't easily find a quotation or page reference when you are writing an essay or thesis.
It is also essential that you keep a record so that you can give proper accreditation to any sources you use to build your written argument. If you don't cite an idea or direct quotation, you could be accused of plagiarism. This has serious consequences for your degree. Find out more about avoiding this on the Plagiarism LibGuide.
Harvard? APA? MHRA? Different subjects like you to cite resources according to different conventions. You can find out how your department prefers you to cite and reference by looking at the Reference Management LibGuide.
Imagine you are looking for a book and your supervisor has only provided you with the title. Think how frustrating that would be as you wade through the tens of books with the same name or trying to guess which edition they are referring to. How tricky would it be to track down a direct quotation if you weren't given any page numbers? This is why you need a full a reference on a reading list.
It is also why academic staff need full references in your essays or papers, so that they can see where you have sourced your ideas and words. You'll need to provide the following information. This is the Harvard style and you find out how to craft more complex references on Cite them Right or the Economics LibGuide - use the concertina menu on the right hand side for drop down examples.
Your department may ask for it in a different order or with different punctuation. Check your departmental style guide.
You need to take records of everything you encounter during the research process. You can do this in a notebook, but you'll soon find that unwieldy. Reference management software will let you download references from catalogues and databases, store pdfs and take notes, keeping everything in the same place and searchable so you can track it down later.
Both Mendeley and Zotero are free software that enable to you download, store and annotate references and documents. One of the most useful aspects lets you cite references in a document and automatically builds your bibliography/list of references.
If you are looking for something less involved, why not try Zoterobib. This lets you add a title, ISBN, DOI, PMID or URL to quickly generate a formatted reference or bibliography. You can effortlessly change reference style too. You don't need to create an account; just create and export it straight to your work. The unique link will let you return to it later or share with someone else.