文档对象模型 

标准化
W3C对DOM进行标准化的动作，目前已经推行至。

Level 1
Document Object Model (DOM) Level 1 Specification 支持XML 1.0 Level 2
Document Object Model (DOM) Level 2 Core Specification XML 1.0与名字空间
Document Object Model (DOM) Level 2 HTML Specification HTML 4.0x、XHTML 1.0
Document Object Model (DOM) Level 2 Views Specification
Document Object Model (DOM) Level 2 Style Specification 支持CSS与CSS Level2
Document Object Model (DOM) Level 2 Events Specification 支持HTML 4.01
Document Object Model (DOM) Level 2 Traversal and Range Specification Level 3
Document Object Model (DOM) Level 3 Core Specification
Document Object Model (DOM) Level 3 Load and Save Specification
Document Object Model (DOM) Level 3 Validation Specification Level 4
Document Object Model (DOM) Level 4