If you want to significantly expand your web development skills beyond PHP, this practical, hands-on book teaches you ECMAScript - the core JavaScript language - from the ground up. You'll discover some similarities between JavaScript and PHP, such as conditions and loops, but the primary focus is on JavaScript's unique object creation, classes, prototypes, and inheritance. JavaScript knowledge is essential for working with today's Web, whether you're building applications for the client, the server, or for mobile use - and your PHP experience gives you a head start. This book will help you become fluent with JavaScript quickly, and then serve as a handy reference once you start coding. Explore JavaScript syntax, including variables, arrays, loops, and conditions Learn how functions are important in JavaScript - and why they're actually objects Delve into JavaScript's object-oriented features, including prototypes, code reuse, and inheritance Examine the built-in API and explore its global functions, properties, and objects Learn about updates in ECMAScript5, the latest version of the standard Use common design patterns to organize your code in large applications