说明：  从浅入深的介绍了JavaScript高级程序设计的内容，包括变量、作用域、引用类型、函数表达式、DOM 扩展，事件，canvas绘图，html5脚本编程， ajax与comet等详细介绍。
(The content of JavaScript advanced programming is introduced from shallow to depth, including variables, scopes, reference types, functional expressions, DOM extensions, events, canvas drawing, HTML5 scripting programming, Ajax and comet.)