问题 To run applications in Azure, I need to create an Application in Azure AD and a corresponding Service Principal. Then my application authenticates against this App/Principal pair. To authenticate, I can create an application key in the App registration, or I can create a password in the Service Principal (among other options). What's the difference from a practial standpoint? For example, this code runs exactly the same (from the outside) whether the $key is the App's key or the Service