全书从Javascr ipt 语言实现的各个组成部分——语言核心、DOM、BOM、事件模型讲起，深入浅出地探讨了面向对象编程、Ajax 与Comet 服务器端通信，HTML5 表单、媒体、Canvas（包括WebGL）及Web Workers、地理定位、跨文档传递消息、客户端存储（包括IndexedDB）等新API，还介绍了离线应用和与维护、性能、部署相关的最佳开发实践(The book from every part of the Javascr ipt language - the language of DOM, BOM, core, event model talk, the method of object oriented programming, Ajax and Comet server communication, HTML5 form, media, Canvas (including WebGL) and Web Workers, geographic location, cross document delivery message, the client storage (including IndexedDB the new API), and also introduced offline applications and related performance, deployment and maintenance, development best practice)