The document provides an introduction to object oriented programming in PHP, explaining key concepts like classes, objects, properties, methods, encapsulation, and inheritance. It uses examples like a social networking profile class to demonstrate how to create classes with properties and methods, instantiate objects, and extend classes through inheritance. The document also discusses benefits and drawbacks of the object oriented approach.

1. Beginners Guide to Object Orientation In PHP by Rick Ogden for PHPNW09

2. What is Object Orientation? Object-Oriented Programming is a programming methodology that consists of multiple interacting objects, each completely self-sufficient. This allows for flexible, expandable programming

3. Encapsulated code

4. Protection of data

5. Many more things beyond the scope of this tutorial

6. Class A class is a blueprint of an object, and is the basis of what the object will consist of. It contains two major entities: Properties

7. Methods

8. A class is self sufficient by nature, and therefore can be implemented into multiple applications without modification.

9. Example of a Class Here we're going to create a new class for containing someone's profile information on a social networking website.

10. Object An object is created by creating a new instance of a class. Objects of the same class have exactly the same functionality, but the properties within the object are what makes them different. Eg. A news article on a website may be an object from a NewsArticle class, but the contents of the article will differ from another news article

11. Referencing In order for an object to be useful, you need to be able to call its contents. For this, PHP uses the arrow operator ( -> ). $object->property;

12. $object->method();

13. Self Referencing Throughout the instance of an object, chances are it will need to reference itself (to get its properties, or call its own methods). In order for an object to reference itself, the variable $this is used in the class. $this->property;

14. $this->method();

15. Properties Properties are class-wide variables.

16. They are often initialised when an object of the class is created (although they do not have to be)

17. They are defined at the top of the class

18. Methods can alter and interact with these properties throughout the existence of the object

19. Adding Properties We will add some properties to our Profile class. Of course the properties are not limited to the ones here:

20. Methods A method is a piece of code within a class which performs a task or calculation. These are similar to functions. It can: Interact and modify properties of the object

21. Take arguments on execution

22. Return a value after execution