parameter in roue laravel code example

Example 1: laravel route

Route::get('user/{id}', function ($id) {
    return 'User '.$id;
});

Example 2: laravel route namespace and prefix

Route::get('/user/{name?}', function ($name = null) {
    return $name;
});

Route::get('/user/{name?}', function ($name = 'John') {
    return $name;
});