Collections help you better organize your references. Collections are similar to file folders on your computer; however, in Zotero a reference can be in more than one collection at a time. For example, an article about Virginia Woolf could be filed in your "Women and Writing" collection, your "British Authors" collection, and your "Woolf" collection without having to make multiple copies. You can see your collection on the left side of your Zotero 7 Standalone or online.

1. Open Zotero online or Zotero 7 Standalone.
2. At the top left is a plus sign (for Zotero online, it is right next to "My Library" as a hidden plus sign icon; for Zotero Standalone, it is a folder with a plus sign in the bottom left-hand corner).
3. Click on this and create a name for the collection.
4. Drag and drop references to the collection name in the left sidebar. 

You will find information Zotero has collected about your references on the right side of your library. Bibliographic information, like author, journal title, page number, publication year, etc. can be found in the 'Info' tab. By clicking on any field you can change the information or add to it. The only fields you cannot edit under 'Info' are 'Date Added' and 'Modified.'

• Notes - use the notes field to attach notes to your record, such as quotes, summaries, or why you chose to cite it.
• Tags - tagging items with keywords makes it easier for you to search your citations. Tags are often automatically downloaded from databases and catalogs, but you can also create your own. 
• Related - link to other items in your collection. This can be useful for demonstrating how citations are connected to one other.

If there is a PDF with an article citation, Zotero will often save the PDF automatically to the citation. If it does not save automatically, check your Zotero Preferences. To attach items in your Zotero library, you must change your Zotero settings.

1. Open Zotero 7. 
2. On Windows click on "Edit" and then "Settings," and on Mac click on "Zotero" at the top of your screen, and then "Settings."
3. Click on the General pane, indicated by a gear. 
4. You will see a list of options under "File Handling." Make sure that box is checked next to the option: "Automatically attach associated PDFs and other files when saving items."

You can also attach files and PDFs manually to citations. 

1. Open Zotero Online or Zotero 7 Standalone.
2. Navigate to the citation to which you want to attach files.
3. Right-click the file and select "Add attachment," which will allow you to attach a link, screenshot, or file. 

If you have a collection of previously downloaded PDFs on your computer, Zotero can help you add citation information for them. To add PDFs to Zotero and find their metadata, use the following steps:

1. Open Zotero online or Zotero 7 Standalone.
2. For Zotero online, click on the "Add Item" icon. For Zotero 7 Standalone, click on the "Add Attachment" icon located on the left of the "Add Item(s) by Identifier" wand icon.
3. From the drop down menu, select "Upload File." for Zotero online and "Add File." for Zotero 7 Standalone.
4. Select your PDF and click 'Open.'
5. You will now see the PDF included in your Zotero library. Find it in your list of items, and right click it.
6. From the menu options, select "Retrieve Metadata for PDF." 
7. Zotero will search the web to attempt to find citation information for your document. You will see a dialog box where it indicates whether it has been successful. 
8. If the search is successful, you will see your PDF is now attached as part of a regular citation in your Zotero library. Repeat as needed to get all of your old PDFs included in your collection!

For more on how this process works, read on Zotero's retrieve metadata guide.