Citation management software such as RefWorks, EndNote, Zotero, and Mendeley, all have the capability of adding full text PDF files of journal articles within their respective databases. This can be useful when you don't want to wait for the "link out" to the full text to find the article. But this feature, designed to be a helpful feature, actually become problematic when too many articles are added to you collection of citations. Each PDF may add anywhere from 200K to well over a megabyte of space to your bibliography. I have heard of databases crashing because the files become corrupt. The video in this guide discusses best practices when it comes to storing these files in your citation software.