title: How does Azure PowerShell work with username/password based auth?
body: <p>I want to understand how Azure PowerShell makes Azure API calls using AAD username/password based credentials. </p>
  
  <p>My understanding is that an app needs a client-id before it can make Azure API calls. This client ID must be registered with a user’s account. </p>
  
  <p>Does Azure PowerShell have a client-id? If so, how does it work without explicitly registering it with Azure accounts? Is it a special id that has been whitelisted across accounts?</p>