Zotero provides the ability to save references from most library catalogs and databases, and even some regular web pages, with one click. If Zotero detects that you're looking at a book or article on a catalog, database, or a site like Amazon.com, WorldCat or the New York Times, you'll see a book or page icon appear in the address bar of your browser. Just click the icon and Zotero will automatically save the citation.
If you're on a page of search results with many items, you'll see a folder icon instead. Click this to get a list of all the items on the page, and check off the ones you want to save.
Zotero can't automatically capture citation info from some web pages, but you can still add them to your Zotero library.
Click the Zotero button at the bottom of your browser to access Zotero's controls.
Click the page button (to the right of the green plus sign) to save a link to the page. This will save a new "web page" item to your library. You can add information about the author, etc., if you wish.
This will also attach a snapshot of the page to the citation. Taking a snapshot saves a copy of the page to your computer. It includes the page's text and images, so if the page is removed later, or if you're offline, you'll still be able to view your copy.
To add an attachment, such as a PDF, to a saved citation:
Click on the New Child Attachment icon () in the Middle Panel and choose from the drop-down menu:
Select "Attach Stored Copy of File..." to attach a PDF to a saved citation.
The PDF will appear nested below the citation in the center panel.