Question: I am a newbie to the codeigniter while I was wrkng with the CI, I got some error as follows:

> 
> **Fatal error: Class 'Controller' not found in C:\wamp\www\CodeIgniter\application\controllers\Hello.php on line 3**
> 
> 
> 

```
Call Stack
#   Time    Memory  Function    Location
1   0.0237  150568  {main}( )   ..\index.php:0
2   0.0425  186632  require_once( 'C:\wamp\www\CodeIgniter\system\core\CodeIgniter.php' )   ..\index.php:202
3   0.3513  658176  include( 'C:\wamp\www\CodeIgniter\application\controllers\Hello.php' )  ..\CodeIgniter.php:250

```

This is the error I got. In the controllers folder I saved my `Hello.php` which had the following contents:

```
class Hello extends Controller
{
    function Hello()
    {
        parent::Controller();
    }

    function you()
    {
        $this->load->view('you_view');
    }
}

```

and in my view folder I saved my `you_view.php` which had the contents as:

```
Hello, you!

```

I can't clear these errors pls help me. Thanks in advance.

Answer: 
The default in codeigniter is this:

```
// CI_Controller not Controller
class Hello extends CI_Controller
{

    public function __construct()
    {
        parent::__construct();
        // constructor codes etc.
    }

    public function you()
    {
        $this->load->view('you_view');
    }
}

```
First find out what version of codeigniter you are using if this is 2+ then your syntax is wrong it should be

```
class Hello extends CI_Controller
  {
      function Hello()
      {
          parent::Controller();
      }

      function you()
      {
          $this->load->view('you_view');
      }
  }

```

the `class Hello extends Controller` works only on below version of codeigniter 2.. Hope this will help you