Zotero provides the ability to save references from most library catalogs and databases, and even some regular web pages, with one click. (Zotero publishes a list of compatible sites, and many sites not on this list also work.)
If Zotero detects that you're looking at a book or article on a catalog, database, or a site like Amazon.com, LibraryThing 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.
The book icon will change depending on what type of source you are looking at.
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.
Other Web Sites
Zotero can't automatically capture citation info from some web pages, but you can still add them to your Zotero library.
Click the Page button at the top right of your browser to access Zotero's controls. 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.
It's easy to attach files (like PDFs) to items in your Zotero library. Just drag the file into your Zotero pane.
Each item also has an Attachments tab in the right column. Attach files by clicking the Attachments button (the paper clip) and then selecting the type of attachment you want to add.
Click the Zotero button at the bottom of your browser to open your library. At the top left is a folder button with a green plus sign. Click this to create a new "Collection."
Create collections to organize your references. Collections are like file folders on your computer, but a reference can be in more than one collection at a time. In other words, a book on the Civil War could be filed in your "Civil War" collection, your "Georgia History" collection and your "19th Century America" collection without having to make three copies of the reference.