The focus on this guide is the usage of Doppelgänger, which covers interaction with the system to perform tasks like:
Creating things using the REST API.
Publishing data that gets mapped to things.
Viewing the state of your things.
Setting desired state of things that gets reconciled.
In the Overview section, you will find chapters about the Concepts and High Level Architecture. Be sure to get a basic understanding of Doppelgaenger before reading this document.