How does a hook work?

[eluser]nirbhab[/eluser]
here is sample hook, hope it helps you out.

Code:

<?php
if (!defined('BASEPATH')) exit('No direct script access allowed');
class getSystem
{
    function check()
    {
$CI =& get_instance();
$CI->load->helper('date');
//below code in not tested, according to concept, but above is running fine.
$CI->value="some_data";
//hope you can access this data in controller or model or view by $this->value
    }
}
?>