Object Oriented Programming

languages like java are purely OOP

PHP is a scripting language that has a bit of HTML, OOP and logic

Basic OOP

Drupal started at a time when object oriented programming ...

4 basic Principles of OOP

1. Polymorphism
2. Abstraction
3. Encapsulation
4. Inheritance

Glossary

Class - An encapsulation of some functionality

Subclass - An extension to a base class that inherits the base classy functionality but adds more

Property - A property of a class that represents a value

Function - Some logic that either modifies a property or returns some value

Exercise

Create shape classes in PHP

<?php

//base class
class Shape {

declare the base class. Other classes can be declared within this with different values

const SHAPE_TYPE = 1;

protected means that the value cannot be changed

private means that the value can be changed but it can't be accessed directly.