What Does "use AuthorizesRequests, DispatchesJobs, ValidatesRequests; " in Laravel 5.6 Default Controller do?

What is the use of:

use AuthorizesRequests, DispatchesJobs, ValidatesRequests;

in default laravel controller.

Also, why we do it inside class when we already have:

use Illuminate\Foundation\Bus\DispatchesJobs;
use Illuminate\Foundation\Validation\ValidatesRequests;
use Illuminate\Foundation\Auth\Access\AuthorizesRequests;

via Chebli Mohamed