class Database {
  protected $userName;
  protected $password;
  protected $dbName;

  public function __construct ( $UserName, $Password, $DbName ) {
    $this->userName = $UserName;
    $this->password = $Password;
    $this->dbName = $DbName;
  }
}

// and you would use this as:
$db = new Database ( 'user_name', 'password', 'database_name' );

class Person {

    public function __construct() {
        // Code called for each new Person we create
    }

}

$person = new Person();

class Person {

    public $name = '';

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

}

$person = new Person( "Joe" );
echo $person->name;

class Cat
{
    function Cat()
    {
        echo 'meow';
    }
}

class Cat
{
    function __construct()
    {
        echo 'meow';
    }
}

$cat = new Cat();

class Cat
{
    function Cat()
    {
        echo 'meow';
    }
}

class cat {
    function speak() {
        echo "meow";
    }
}

include('class_cat.php');
mycat = new cat;
$speak = cat->speak();
echo $speak;