Zotero (pronounced "zoh-TAIR-oh") is an open source, free citation management tool for collecting and organizing references, and can generate bibliographies in almost any citation style. Zotero also allows you to store and annotate PDFs, and attach notes and images to your citations. 

To use Zotero, register for an account at Zotero.org or download Zotero Desktop and Zotero Connector, a browser extension compatible with Chrome, Firefox, or Safari. Zotero Desktop includes plugins for MS Word, Google Docs, and OpenOffice, so you can "cite while you write."

The Zotero Connector can import the resource(s) you are viewing online (articles, books, and webpages, database results, and more) into your Zotero library, to easily save references during your research process. 

Zotero.org: register for a Zotero account, access downloads, work with your online Zotero library.

Zotero documentation and support: resources to help with all aspects of Zotero usage, from installation and getting started to troubleshooting and advanced features; access to active Zotero user forums.

Vassar Zotero guide: Vassar-specific help, this guide also includes details about how to set up and use Zotero "groups" for collaboration.

ZoteroBib: Zotero's quick cite tool for when you need to quickly get a citation; generate a citation with a URL, ISBN, DOI, PMID, arXiv ID, title, or manually enter item details. 

Zotero Desktop is a good option if you:

• want to use the Zotero Connector tool. 
• plan to use Zotero extensively and want to the more robust version.
• want to insert citations and bibliographies into MS Word, Google Docs or LibreOffice documents.
• have a large library of citations and need the extended storage space your computer provides.

Zotero Online is a good option if you:

• have a smaller reference library and do not plan to utilize more advanced Zotero features.
• have a Chromebook, or other type of laptop/device that does not allow software installation.

You can install Zotero Desktop and use Zotero Online. Make sure to use the "sync" button in the upper right of the web version and Zotero Desktop and sign in so that your citations sync between them.