Zotero is a free tool that collects, manages, and cites research sources. It's easy to use and lives in your web browser where you do your work.
The Firefox version can be used in both PCs and Macs and is generally considered the easiest to install and use.
Zotero allows you to attach PDFs, webpages, article citations, and organize them into easily searchable collections for different projects, and create bibliographies using Word (for Mac or Windows). The Groups feature allows you to share a file of citations and documents with a group of people working on the same project.
References can be added to a Zotero library in many different ways: directly from databases, journal websites, amazon, Google Scholar, the library catalog, or even manually typing them in.
One of the most useful things about Zotero is its integration with Microsoft Word (and some other word processors.) The new 5.0 version of Zotero claims to automatically download a plug-in that will cooperate with your word processor. If this doesn't happen, you may need to do it manually. The help documentation and download instructions are here: https://www.zotero.org/support/word_processor_plugin_installation
Zotero 5.0. A brand new version of Zotero (as of August 2017). This will soon be the ONLY version of Zotero, which will ultimately simplify things. If you are new Zotero, this is the version you should download, regardless of your preferred browser.
The Firefox Plug-in. Zotero was designed for Firefox, so the plug-in has the greatest functionality and ease of use. Your work will be stored in the clouds, so you will be able to access it anywhere. It works with both Macs and PCs, so if you are a user of Firefox, this is the easiest way to go. As you download the software, you will be prompted to also download a plug-in to communicate with Microsoft Word. I recommend you download it if you intend to use Zotero for generating a bibliography.
Choose the Zotero Standalone if you are committed to using Safari or Chrome. It has most of the same features, but it runs as a separate program instead of part of your web browser. You must also download a “Connector” which will live in your browser and make it easier to use. The plug-in for communicating with Microsoft Word is included when you download the connector.
Neither the plug-in or the stand alone versions are compatible with Internet Explorer.
This is an excellent, 4 minute video that walks you through installation and basic skills for both Mac and PCs.
If you would like the ability to share notes, sticles, and citations with a group of people, Zotero will allow you to designate a shared file.
If you need more help setting up a group than this video provides, here is a good website to consult