Sometimes it is important to only work on copies of objects - you might not want to affect the state of the original. To do this, we use the built-in keyword "clone", which performs a complete copy of the object
Internally, the clone keyword copies all the variables from the first object to a new object, then calls a magic function __clone() for the class it is copying. You can override __clone() if you want, thereby giving you the flexibility to perform extra actions when a variable is copied - you can think of it as a constructor for copied object
class MyClass
{
public $name = 'MyClass';
public function __clone() {
$this->name .= '++';
}
}