Action Pack

The controller and view of the RubyOnRails MVC-Framework is handled 
by the Action Pack, which handles both layers by its two parts: 
Action View and Action Controller. These two layers are bundled 
in a single package due to their heavy interdependence. This is unlike 
the relationship between the Active Record and Action Pack that is 
much more separate. 

Each of these packages can be used independently outside of Rails.

WWW: http://www.rubyonrails.org