parent:: AND self::

PHP supports two reserved class names that make it easier when writing OO
applications. PHP supports two reserved class names that make it easier when writing OO
applications. self:: refers to the current class and it is usually used to access
static members, methods, and constants. parent:: refers to the parent class and
it is most often used when wanting to call the parent constructor or methods.

• self:: refers to the current class and it is usually used to access
  static members, methods, and constants.
• parent:: refers to the parent class and
  it is most often used when wanting to call the parent constructor or methods.
•  It may also be used to access members and constants.


class Ancestor {
const NAME = "Tran Dinh Trong";
function __construct() {
print "In ". self::NAME." Construct";
}
}
class Child extends Ancestor{
const NAME = "Tran Dinh Thien";
function __construct() {
parent::__construct();
print "In ".self::NAME." Construct";
}
}
$child = new Child();


In Tran Dinh Trong Construct

In Tran Dinh Thien Construct