Assets are things that you upload or create in Pebble+. You can upload any type of digital file using the Upload new option. All uploaded files are Assets and can be found in your Asset Store. You can also create things in Pebble+ from Get creative (on the homepage or from the Burger menu), or by using templates or workbooks from the Resource store. When you Save any of these things they become Assets in your Asset Store. Assets contain personal content - content that you have added, that is meaningful to you, and that you can go back and edit or delete as required.
If you would like to view a short video explaining the difference, please see our Help topic on Assets vs Resources.