What is the responsibility of Front Controller?

Q. What is the responsibility of Front Controller?

Directly receive the request from browser.
All requests call the function Mage_Core_Controller_Varien_Front::dispatch()
– URL rewriting process.
– Load the module and action controller corresponding with the requests through routers to process the requirements which are sent from clients.

Collect routers: admin, standard, default.
Use the function match() of routers to define the module and controller that are requested.
Call the function dispatch() of the controller requested.
Call the action requested.
– Return HTML for browser

Call the function sendResponse() of Mage_Core_Model_Response_Http (extend from Zend_Controller_Response_Abstract).
Call the function sendHeaders() – use the header() function of PHP.
Call the function outputBody() to show the whole content of the body part:
echo implode(”, $this->_body);