guides/authentication.md

@@ -65,10 +65,11 @@ If you can't use this class or don't want to then you don't have to, provided yo
 
 ## Preparing the User Model
 
-your user model must extend `DjangoLDP.Model`, or defines a `urlid` field on the user model, for example:
+For federated login to work, your user model must extend `DjangoLDP.Model`, or define a `urlid` field on the user model, for example:
 ```
 urlid = LDPUrlField(blank=True, null=True, unique=True)
 ```
+If you don't include this field, then all users will be treated as users local to your instance
 
 **Why?**