constructor

The constructor is a special method in a class, which is called at instantiation of an object, with the provided arguments.

In PHP, parents constructors are not automatically called, when a child class defines a constructor. They have to be called manually.

<?php

class X {
    private $property;

    function __construct($value) {
        $this->property = $value;
    }
}

$x = new X(1);

?>

Documentation

Related : Destructor