what is build command in laravel code example

Example 1: how create new command in laravel

php artisan make:command SendEmails

Example 2: laravel create command tutorial

use App\Models\User;
use App\Support\DripEmailer;

Artisan::command('email:send {user}', function (DripEmailer $drip, $user) {
    $drip->send(User::find($user));
});