文档模式是浏览器用来呈现页面的方式:IE9、IE8、IE7 或 Quirks.浏览器模式设置浏览器如何向 Web 服务器和 JavaScript 标识自己.

Document Mode is what the browser uses to render the page: IE9, IE8, IE7 or Quirks. Browser Mode sets how the browser identifies itself to the web server and to JavaScript.

从测试的角度来看，这似乎是不必要的混淆，因为这是两个单独的选项，您通常想要更改这两个选项，例如，将浏览器模式设置为 IE8，将文档模式设置为 IE8，以使 IE9 伪装成 IE8.

From a testing standpoint, it seems unnecessarily confusing that these are two separate options and you usually want to change both, for example, set the Browser mode to IE8 and the Document Mode to IE8 to get IE9 to pretend to be IE8.

还有用于浏览器模式的 Internet Explorer 9 兼容性视图选项.这似乎与 IE7 模式相同，只是用户代理字符串还显示Trident/5.0"(Trident 是 IE 布局引擎).

There's also the Internet Exploer 9 Compatibility View option for Browser Mode. This seems to be the same as IE7 mode except the user-agent string also says "Trident/5.0" (Trident is the IE layout engine).