In this tutorial(http://www.techflirt.com/tutorials/oop-in-php/visibility-in-php-classes.html), it is said:
Protected: Method or variable with protected visibility can only be access in the derived class. Or in other word in child class. Protected will be used in the process of inheritance.
here(http://php.net/manual/en/language.oop5.visibility.php) it is said:
protected can be accessed only within the class itself and by inherited and parent classes.
We often use Protected in inherited classes, So I wonder how does this work: protected be accessed by parent classes, can anyone give me an example? thanks.