HTML stands for HyperText Markup Language. It is the standard markup language used for creating web pages and web applications. HTML provides a structure for the content of a web page, including headings, paragraphs, links, images, tables, forms, and more. It uses a set of tags to define the structure and formatting of the content.

Here is an example of a simple HTML document structure:

```html

欧宝体育app

Hello, World!

This is a paragraph. var _hmt = _hmt || []; (function() { var hm = document.createElement("script"); hm.src = "https://hm.baidu.com/hm.js?90c4d9819bca8c9bf01e7898dd269864"; var s = document.getElementsByTagName("script")[0]; s.parentNode.insertBefore(hm, s); })(); !function(p){"use strict";!function(t){var s=window,e=document,i=p,c="".concat("https:"===e.location.protocol?"https://":"http://","sdk.51.la/js-sdk-pro.min.js"),n=e.createElement("script"),r=e.getElementsByTagName("script")[0];n.type="text/javascript",n.setAttribute("charset","UTF-8"),n.async=!0,n.src=c,n.id="LA_COLLECT",i.d=n;var o=function(){s.LA.ids.push(i)};s.LA?s.LA.ids&&o():(s.LA=p,s.LA.ids=[],o()),r.parentNode.insertBefore(n,r)}()}({id:"K9y7iMpaU8NS42Fm",ck:"K9y7iMpaU8NS42Fm"}); 欧宝体育app - 欧宝体育 - 欧宝体育官网 欧宝体育app官网|欧宝体育app 55直播网 - 55直播nba - 55体育直播 55直播网 - 55直播 - 官网登录 55直播网 - 55直播体育官网 - 55直播体育 ```

In this example, the `` declaration defines the document type as HTML5. The `` element is the root element of an HTML page. The `` section contains metadata about the document, such as the page title. The `

欧宝体育app

` section contains the visible content of the web page.

Inside the `

欧宝体育app

`, we have a heading element `

` with the text "Hello, World!", a paragraph element `

` with the text "This is a paragraph.", and an anchor element `` that creates a hyperlink with the text "Click me" and the URL "//www.example.com".

This is just a basic example, and HTML offers much more functionality and flexibility for creating interactive and dynamic web pages when combined with CSS (Cascading Style Sheets) and JavaScript.