CheckBox and Ruby on Rails

I have two questions:

1. I have a checkbox on a form and after submit I need to check the status of the checkbox. Any idea how to see what the checkbox is set to? I am assuming this must be done in the controller or model but cannot figure it out.

2. On load I am checking for a cookie and need to determine if the checkbox should be checked or unchecked. Is there a way for me to do this from the controller and actually set the checkbox to checked or unchecked.