The SOLIDWORKS Design Library in the SOLIDWORKS Task Pane provides quick access to some default features, hardware, annotations, etc. This is also where you have access to:
But you can add additional library folders for quick access to your parts and assemblies. This can be handy if you have a folder of standard parts or just to add the folder of your active project. You can drag the components into your assemblies, or double-click to open the files.
Here is an example of adding the folder of your active project to save you from browsing through the directories to find it.
You can right-click in the preview window to change the view options.
The file locations are stored in the System Options. You can add and delete these references through this interface as well. This will only remove the reference. It will not delete the files or folder from your machine.