 ,       . 
       ,    PHP   ->. 

 :

<?php
//    Coor:
class Coor {
//  ():
var $name;
// :
 function Getname() {
 echo "<h3>John</h3>";
 }

}

//    Coor:
$object = new Coor;
//     :
$object->name = "Alex";
echo $object->name;
//  'Alex'
//        (,    ):
$object->Getname();
//  'John'  
?>
       , 
   $this,      . 
  Getname():

function Getname() {
echo $this->name;
}
  ,    Setname():

function Setname($name) {
$this->name = $name;
}
       Setname():

$object->Setname("Peter"); 
$object->Getname();
     :

<?php
//    Coor:
class Coor {
//  ():
var $name;

// :
 function Getname() {
 echo $this->name;
 }

 function Setname($name) {
 $this->name = $name;
 }

}

//    Coor:
$object = new Coor;
//       Setname():
$object->Setname("Nick");
//   ,   , Getname():
$object->Getname();
//   'Nick'
?>
 $this       ,       :

function Setname($name) {
$this->name = $name;
$this->Getname();
}