Another concern is:
What is the Difference between controller and Blocks ?
Solved! Go to Solution.
Please cehck following thread:
Below is the main difference between controller and block !
Block are responsible for rendering content (everything from frontend, backend, emails, and more). If content is being displayed somewhere chances are it is a block.
controllers are responsible for processing all requests made via a url. If you hit the url http://www.example.com/catalog/product/view/id/9/ you hit the catalog module in the controllers/ProductController.php and inside of that the viewAction() method. If you hit a URL in Magento the request passes through one or more controllers.
For more details refer below links :
Hope it helps !