how laravel extends class without including them - php

Question

I encountered the topic called 'namespace' in php after I started working with Laravel. While trying to understand namespace I found that to extend a class under a namespace, I need to include that class in my current page. Like the following:
directory '..\teacher\Teacher.php'
namespace Teacher;
class Teacher{
public $headTeacher='mr X';
}
to extend the calss i need to include that page as well as use the namespace
directory '..\studnet\student.php'
use \Teacher\Teacher; //use the namespace
include('../teacher/Teacher.php'); // include the page
class mathTeacher extends Teacher{
public function headTeacherName(){
echo $this->headTeacher;
}
}
$student=new mathTeacher();
$student->headTeacherName();
I am wondering how Laravel only use namespace to include classes. Like if I create a controller called 'userController'. The structure of the page is
namespace App\Http\Controllers;
class userController extends Controller{
}
They never included the php page which holds the 'controller' class. But they were able to extend it somehow. Also I can use "View" ,"Auth" just by using the use View or use Auth command. How is it done? How can I implement the same with the code I have provided? Thanks in advance.

Answer 1

Laravel uses composer.php for autoloading the classes. All classes in the autoload directory will be pre loaded. So you can just use the namespace and consume anywhere across the application.
Learn more about composer, composer config can be found on composer.json in your root path for the application