Rules is a powerful module that is used to automate actions on your Drupal site which has the fundamental concepts of "Event-Condition-Action” rules. Rules can react on events occurring on your site, evaluate conditions (if specified) then execute an action.
In this series you will learn the basic workflow of the Rules Module. I will also walk you through creating a new rule and show you how to add an action to the new rule that will notify the author of an article when a comment is posted on their article. Lastly, I’ll show you how to create another rule that will notify the comment author when someone replies to their comment.