JavaScript

JavaScript由三部分组成：

1. the core (ECMAScript)
2. the Document Object Model (DOM)
   • DOM是HTML Document node的一个映射，目的是为了方便developer更好地控制和操纵HTML Document。
3. the Browser Object Model (BOM)
   • BOM allow access and manipulation of the browser window.
   • this is the only part of a JavaScript implementation that had no related standard.
   • with HTML5, it is more standardized than before.
   • example: navigator, location, screen, XMLHttpRequest, cookie