title: Rails - Associations - What am I referring to?
body: <p>I'm new to Rails and have been struggling with the naming conventions to work out what I'm actually referring to. With many items named very similarly (e.g. model class, db table, controller) it isn't always obvious from the examples which object is being referred to.</p>
  
  <p>In the <a href="http://guides.rubyonrails.org/getting_started.html#creating-new-posts" rel="nofollow">guides</a> for associations, it uses posts and comments as examples. Can you help me understand what is actually being referred to?</p>
  
  <p>With the association
     <code>has_many :comments</code>
  What is <code>:comments</code>? Is this the model class or the controller?</p>
  
  <p>When referring to the associated object:
      <code>@post.comments.build</code>
  What is <code>comments</code> in this example? Is it the class, the controller, or the instance variable?</p>