Book excerpt: Build server-side applications more efficiently—and improve your PHP programming skills in the process—by learning how to use design patterns in your code. This book shows you how to apply several object-oriented patterns through simple examples, and demonstrates many of them in full-fledged working applications. Learn how these reusable patterns help you solve complex problems, organize object-oriented code, and revise a big project by only changing small parts. With Learning PHP Design Patterns, you’ll learn how to adopt a more sophisticated programming style and dramatically reduce development time. Learn design pattern concepts, including how to select patterns to handle specific problems Get an overview of object-oriented programming concepts such as composition, encapsulation, polymorphism, and inheritance Apply creational design patterns to create pages dynamically, using a factory method instead of direct instantiation Make changes to existing objects or structure without having to change the original code, using structural design patterns Use behavioral patterns to help objects work together to perform tasks Interact with MySQL, using behavioral patterns such as Proxy and Chain of Responsibility Explore ways to use PHP’s built-in design pattern interfaces