My aim is to teach you the javascript programming language and what you can do with it. javascript is a fundamental language in web design, together with jQuery and AJAX and this guide aims to take you through the language and how to get started in responsive web design. We start by meeting the javascript language head-on. This will take up around half of the book as we go through the fundamentals of the language with full coding examples to help you understand what it's all about. This includes a practical example for you to follow and a quick look at JSON and client-side APIs. Next, we will look at jQuery and AJAX and how they work together. We’ll see exactly what they can do and, again, there will be plenty of code examples to help you.