Simple class extension example.

gistfile1.php

<?php

class Organ {
	
	public function __construct($name){
		$this->name = $name;
	}
	
	public function kill(){
		echo $this->name.' died!<br/>';
	}
	
}

class Limb extends Organ {
	
	public function snap(){
		echo $this->name.' snapped!<br/>';
	}
	
}

class Arm extends Limb {
	
	public function punch(){
		echo $this->name.' threw a punch!<br/>';
	}
	
}


$organ = new Arm('Left Arm');;
$organ->punch();
$organ->snap();
$organ->kill();

?>