Welcome!
This book is a general overview of how to take advantage of jQuery's ease-of-use to make your PHP applications more "snappy" on the client side.
The book is aimed at the PHP developers who usually don't write client-side JavaScript, and would like an example-based introduction demonstrating a wide variety of integrations between server-side and client-side code.
For years, JavaScript (the language that jQuery is written in) has been seen as a "toy" language. However, the pervasiveness of Ajax has allowed it to break out of the client side and become an essential tool for all serious web application developers.
Ajax is a tool used by client-side code to contact the server and get or send data without needing to reload the entire page. It's used to update part of the page, or to retrieve data for a JavaScript application, or to send data to the server. Ajax stands for Asynchronous JavaScript And XML. However, the XML part is optional, and is often replaced with plain text or another data format such as JSON (explained later in this chapter).
This book will demonstrate how combining server-side PHP with client-side jQuery can make JavaScript much more useful than just for "form checking".
It is assumed that you are a server-side web application developer who wants to take a step into the client side and learn how to use JavaScript to make your applications more efficient and exciting for the client.
To be very clear about it, this book is not about PHP, and it is not about jQuery—it is about how to work with both PHP and jQuery. This book will teach you how to use jQuery to create some really cool effects, but without you needing to have in-depth knowledge of how jQuery works.
With this book, we are more interested in providing some practical demonstrations of PHP and jQuery with explanations, than in getting right down into the guts of how JavaScript works and how it is different from PHP.
After reading this book, you will have seen and built a wide variety of example applications. This would certainly be enough to immensely change how your current PHP applications work.
Each chapter in this book is dedicated to a specific subject, and will usually involve building a practical example, which you can use in your day-to-day work.