Whether you need an example-driven programmer's guide or a complete desk reference, JavaScript: The Definitive Guide is the most authoritative book on this language that runs the Web. The sixth edition offers comprehensive coverage of ECMAScript 5 (the new language standard) and also the new APIs introduced in HTML5. The chapters on functions and classes have been completely rewritten and updated to match current best practices. A new chapter covers language extensions and subsets.JavaScript: The Definitive Guide is organized into four sections: Part 1: Learn the core JavaScript language in detail -- ideal for newcomers as well as experienced JavaScript programmers who want to sharpen their skills Part 2: Understand the scripting environment provided by web browsers with broad and deep coverage of client-side JavaScript illustrated by many sophisticated examples Part 3: Get a complete reference for core JavaScript that documents every class, object, constructor, method, function, property, and constant Part 4: Consult a separate reference to client-side JavaScript, including legacy web browser APIs, the standard Level 2 DOM API, the XMLHttpRequest object, and the canvas tag