The Assets panel provides you with the ability to organize the components of your site from within Dreamweaver. You can use it to view and catalog a wide variety of media and page elements. For example, it might be difficult to manage all your images, especially if you are working on a large site. The Assets panel gives you a way to keep track of those images.
Select the Assets panel from the Files panel group. Click the Images button located at the top of the column of buttons on the left side of the Assets panel.
The other buttons along the left side ...
If the Assets panel or Files panel group is not visible, you can choose Window > Assets to open the Assets panel within the Files panel group.