diff --git a/guides/source/form_helpers.md b/guides/source/form_helpers.md
index 2a289dd33afc00e43169fd2e82b9caded434a32f..422bc647efb1b5284d41209ae2efdbc94a961947 100644
--- a/guides/source/form_helpers.md
+++ b/guides/source/form_helpers.md
@@ -317,7 +317,7 @@ The Article model is directly available to users of the application, so - follow
 resources :articles
 ```
 
-TIP: Declaring a resource has a number of side-affects. See [Rails Routing From the Outside In](routing.html#resource-routing-the-rails-default) for more information on setting up and using resources.
+TIP: Declaring a resource has a number of side effects. See [Rails Routing From the Outside In](routing.html#resource-routing-the-rails-default) for more information on setting up and using resources.
 
 When dealing with RESTful resources, calls to `form_for` can get significantly easier if you rely on **record identification**. In short, you can just pass the model instance and have Rails figure out model name and the rest: