You may want to choose Zotero for Firefox if 1) you use the Firefox browser exclusively and 2) you prefer to have Zotero as a pane inside of Firefox rather than as a separate program. Zotero for Firefox runs as a plugin for the Firefox web browser.
Install the Zotero for Firefox plugin.
When you see the message,
"Firefox prevented this site from asking you to install software on your computer," click Allow.
Click Install Now, and Zotero will download and install.
You can either restart Firefox now, or wait until you have installed the word processor toolbar (Step 2).
Word processor plugins allow you to insert citations and bibliographies directly into your documents.
Go to the Word Processor Plugins page. Choose the most recent version of the plugins if you're installing Zotero for the first time.
Word for Mac/Windows users: