diff --git a/core/modules/user/user.install b/core/modules/user/user.install
index 9b70e09fdca64b3655a17570f9063e6ca6ff244e..38d78e132de925526d34cc3078119dc9cdcf39f1 100644
--- a/core/modules/user/user.install
+++ b/core/modules/user/user.install
@@ -120,6 +120,8 @@ function user_schema() {
     ),
   );
 
+  // The table name here is plural, despite Drupal table naming standards,
+  // because "user" is a reserved word in many databases.
   $schema['users'] = array(
     'description' => 'Stores user data.',
     'fields' => array(