HTML <html> 元素 表示一个HTML文档的根（顶级元素），所以它也被称为根元素。所有其他元素必须是此元素的后代。
| 内容分类 | 无 |
|---|---|
| 允许的内容 | 一个 <head> 元素，后跟一个 <body> 元素 |
| 忽略标签 | 如果元素中的第一个元素不是注释，则可以忽略标签。 |
| 允许的父元素 | 无（这是文档的根元素） |
| 允许的 ARIA roles | 无 |
| DOM 接口 | HTMLHtmlElement |
属性
元素包含 全局属性。
manifest- 指定一个 资源清单的URI，指示应在本地缓存的资源。请参阅 使用应用程序缓存 获取详细信息。
version- 指定控制当前文档的HTML版本文档类型定义 。这个属性已不再需要，因为这在文档类型声明中是多余的版本信息。
xmlns-
指派文档的 XML 命名空间。默认的值是
"http://www.w3.org/1999/xhtml"。这在 XHTML 中是必要的，而在 HTML 中则是可选的。
示例
<!DOCTYPE html> <html lang="zh"> <head>...</head> <body>...</body> </html>
可访问性
在html元素上提供具有有效IETF标识语言标记的lang属性，将有助于屏幕阅读技术确定要陈述的正确语言。标识语言标签应描述页面大部分内容使用的语言。没有它，屏幕阅读器通常会默认使用操作系统的设置语言，这可能会导致错误陈述。
规范
| 规范 | 状态 | 注释 |
|---|---|---|
| HTML Living Standard <html> |
Living Standard | （自上一次快照后没有改变） |
| HTML5 <html> |
Recommendation | 为manifest属性增加支持 （后来不赞成）。弃用 version 属性 |
| HTML 4.01 Specification <html> |
Recommendation | 不赞成 version 属性 |
浏览器兼容性
Update compatibility data on GitHub
| Desktop | Mobile | |||||||||||
|---|---|---|---|---|---|---|---|---|---|---|---|---|
html | Chrome Full support Yes | Edge Full support Yes | Firefox Full support Yes | IE Full support Yes | Opera Full support Yes | Safari Full support Yes | WebView Android Full support Yes | Chrome Android Full support Yes | Firefox Android Full support Yes | Opera Android Full support Yes | Safari iOS Full support Yes | Samsung Internet Android Full support Yes |
manifest | Chrome Full support 4 | Edge Full support Yes | Firefox
Full support
3.5
| IE Full support 10 | Opera Full support 10.6 | Safari Full support 4 | WebView Android Full support 4 | Chrome Android Full support 18 | Firefox Android Full support 4 | Opera Android Full support 11 | Safari iOS Full support 3.2 | Samsung Internet Android Full support 1.0 |
version | Chrome Full support Yes | Edge Full support Yes | Firefox Full support Yes | IE Full support Yes | Opera Full support Yes | Safari Full support Yes | WebView Android Full support Yes | Chrome Android Full support Yes | Firefox Android Full support Yes | Opera Android Full support Yes | Safari iOS Full support Yes | Samsung Internet Android Full support Yes |
xmlns | Chrome Full support Yes | Edge Full support Yes | Firefox Full support Yes | IE Full support Yes | Opera Full support Yes | Safari Full support Yes | WebView Android Full support Yes | Chrome Android Full support Yes | Firefox Android Full support Yes | Opera Android Full support Yes | Safari iOS Full support Yes | Samsung Internet Android Full support Yes |
Legend
- Full support
- Full support
- Deprecated. Not for use in new websites.
- Deprecated. Not for use in new websites.
- See implementation notes.
- See implementation notes.
注意事项
- 尽管在 HTML 里<html>元素不是必需的，可以是隐含的，但是在 XHTML 里必须明确给出它的开标签和闭标签。
- 严格意义上，标签是指开始标签（例如 <p> 标签）或结束标签（例如 </p> 标签）；元素（例如 p 元素或者称为
<p>元素）则包括开始标签（自然也包括标签中定义的属性）、结束标签以及中间的内容（Content）。
浏览器兼容性
Update compatibility data on GitHub
| Desktop | Mobile | |||||||||||
|---|---|---|---|---|---|---|---|---|---|---|---|---|
html | Chrome Full support Yes | Edge Full support Yes | Firefox Full support Yes | IE Full support Yes | Opera Full support Yes | Safari Full support Yes | WebView Android Full support Yes | Chrome Android Full support Yes | Firefox Android Full support Yes | Opera Android Full support Yes | Safari iOS Full support Yes | Samsung Internet Android Full support Yes |
manifest | Chrome Full support 4 | Edge Full support Yes | Firefox
Full support
3.5
| IE Full support 10 | Opera Full support 10.6 | Safari Full support 4 | WebView Android Full support 4 | Chrome Android Full support 18 | Firefox Android Full support 4 | Opera Android Full support 11 | Safari iOS Full support 3.2 | Samsung Internet Android Full support 1.0 |
version | Chrome Full support Yes | Edge Full support Yes | Firefox Full support Yes | IE Full support Yes | Opera Full support Yes | Safari Full support Yes | WebView Android Full support Yes | Chrome Android Full support Yes | Firefox Android Full support Yes | Opera Android Full support Yes | Safari iOS Full support Yes | Samsung Internet Android Full support Yes |
xmlns | Chrome Full support Yes | Edge Full support Yes | Firefox Full support Yes | IE Full support Yes | Opera Full support Yes | Safari Full support Yes | WebView Android Full support Yes | Chrome Android Full support Yes | Firefox Android Full support Yes | Opera Android Full support Yes | Safari iOS Full support Yes | Samsung Internet Android Full support Yes |
Legend
- Full support
- Full support
- Deprecated. Not for use in new websites.
- Deprecated. Not for use in new websites.
- See implementation notes.
- See implementation notes.