Reference management software packages can help you:
Create a personal database of references relevant to you, along with associated files.
Insert references into a Word document and format them automatically in a citation style of your choice.
De-duplicate references retrieved from multiple sources.
Share references with others.
There is a range of different software available; UCL Library Services provides support and guidance for Endnote, Zotero and Mendeley. These are all available to download for free or under UCL licences.