When creating a new island in Creative, you have two starting points: starter islands and template islands. While a starter island is basically empty terrain, a template island contains devices and props, and demonstrates how to use them. A template island can be a tutorial, a showcase, or a test environment.
Like sample islands, template islands have been published and have island codes. Unlike sample islands, they can be opened in Creative and edited, and any changes you make while in Create mode will be saved.
Many of the template islands also contain instructions on how to adapt devices to your specific needs.