Tags, Notes and Related Items can be used to better organize your Zotero collections. For example, tags can be used to indicate whether a PDF has already been read and annotated, by adding a Tag "annotated". Tags can be color-coded, which provides a useful visual cue in your list of items in the middle pane as shown below. Notes are another useful feature that allow you to attach an editable notes file to an item.
For more about these features, visit the following links:
With the release of Zotero 6.0, you can now annotate PDFs within the Zotero application, easily saving annotations, highlighted text and comments to notes associated with the item. To annotate a PDF, simple double click on the PDF item from the middle pane of your Zotero application. This will be found by clicking on the small, drop-down arrow next to the parent item as shown.
This will open the PDF annotation tab in your Zotero application. You can use the tools at the top of the pane to highlight text, add notes or capture images of parts of the document. These annotations will appear in the left-hand pane, where you can make edits and add them to Note items.
For more information about how to use these PDFs annotation features, visit Zotero's PDF reader documentation page.
RSS feeds are a useful way to keep on top of blogs, Twitter feeds and other regularly updated content. Zotero has a feature that allows you to follow RSS feeds within your Zotero application. For more information about using Zotero for RSS feeds, visit the Zotero RSS feed support page.