By default, Zotero saves information to your computer, not to the Web. But through its Sync feature Zotero 2.0 allows you to synchronize your citations across multiple workstations. You can also access your library through the Zotero.org website, from anywhere you can access the Web.
To sync your library you'll need to create a Zotero account, if you don't already have one.
To sync your Zotero library:
1. Go to the Middle Panel of the Zotero pane and click the Actions menu icon and select Preferences.
2. In the Sync tab, enter your Zotero Forums username and password.
3. Notice that the Sync Automatically option is checked by default. This will ensure that your library is synced whenever changes are made. You may disable automatic syncing by deselecting the box. To perform a manual sync, click the sync button () near the far right side of the Zotero pane.
Zotero handles citation data syncing and attached file syncing separately. The Zotero website provides more information about file syncing options.