Citation management software allows you to save and organize items found via searching the library's databases. It also can be used to create reference lists and citations for papers. There are a number of software systems available.
Two of the most popular free software management systems are Mendeley and Zotero. Below are some features that may help you decide between the two:
Reasons to choose Mendeley
Your research consists mainly of pdfs. Often this is the choice for researchers in the Sciences.