diff --git a/docs/authentication.txt b/docs/authentication.txt
index 820aff2712..907b72e44a 100644
--- a/docs/authentication.txt
+++ b/docs/authentication.txt
@@ -992,10 +992,10 @@ Writing an authentication backend
 ---------------------------------
 
 An authentication backend is a class that implements two methods:
-``get_user(id)`` and ``authenticate(**credentials)``.
+``get_user(user_id)`` and ``authenticate(**credentials)``.
 
-The ``get_user`` method takes an ``id`` -- which could be a username, database
-ID or whatever -- and returns a ``User`` object.
+The ``get_user`` method takes a ``user_id`` -- which could be a username,
+database ID or whatever -- and returns a ``User`` object.
 
 The  ``authenticate`` method takes credentials as keyword arguments. Most of
 the time, it'll just look like this::