static $protected = false; static function helloworld() { static $var; echo 'Hello world!'; if (true) { static::helloworld(); static::$protected = true; } } public static function wrongKeywordsOrder() { } protected static function wrongKeywordsOrder1() { } private static function wrongKeywordsOrder2() { } public static function rightKeywordsOrder() { } protected static function rightKeywordsOrder1() { } private static function rightKeywordsOrder2() { } } Something::helloworld();