Serenading Complexity into Elegance with Harmonious Traits There is a fundamental problem in programming languages that support Multiple Inheritance. PHP is not one of those languages, but let’s walk through it anyways just so that you understand the issue. Assume there is a parent class that contains a specific method, such as drive. There are two children classes, class 1 and 2, and they each extend the parent class. They inherit the drive method and they override it. Now, PHP doesn’t support what I’m about to tell you since this is a multiple inheritance issue. Another class, class 3, extends

Building Worlds on Abstract Class Pillars Abstract classes  represent abstract concepts. In our previous article, we created various classes that inherited properties and methods from its parent. Looking at the Animal class hierarchy, the Animal class itself is an abstract concept. We can vaguely say Animal, but what type of animal? A Dog may be a narrow enough concept, but a GermanShepherd is definitely a concrete class, not abstract. Abstract classes are classes that start with the word abstract. If a class contains at least one abstract method, it must be declared as abstract. If a method inside of an