What does header definition mean in html?-HTML Tutorial-php.cn

What does header definition mean in html?

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Release： 2023-01-06 11:16:47

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In HTML, the header tag defines the header of the document. The syntax format is "
content
". The header element is a structural element with guiding and navigation functions. It is usually used to place the title of the entire page or a content block within the page.

What does header definition mean in html?

The operating environment of this tutorial: Windows 7 system, CSS3&&HTML5 version, Dell G3 computer.

1. Basic introduction to the header tag element

Before the HTML5 version, it was customary to use div tags to layout web pages. In HTML5, a new header tag element is added based on the div tag. Also called "

" header tag. In the past, we often divided web pages into header, content, and bottom in div css layout. For large structures, we often use divs with ids for layout. The header is often laid out using or . The characteristics are different from the traditional div layout. There is no need for div. tag, but add a new element tag.

It is recognized that "header" is a commonly used name in HTML layout, so a new header tag element is added to HTML5. You can understand why the header is added as a label element in html5.

In addition to using the header tag directly, you can also set class or id to the header.

2. Syntax structure

The header tag element is used the same as div. There is a beginning and there is a closure.

Grammar:

<header>内容</header>

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1. Don’t give id or class directly

<header>头部内容区</header>

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2. Set id

<header id=”pcss5”>头部内容区</header>

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3. Set class

<header class=”pcss5”>头部内容区</header>

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4. Features: Just like the div tag element, it can be used multiple times, and id or class can be used to set different styles in different places.

3. Compatibility

Because the header tag is a new tag element in HTML5, older versions of browsers do not support it. It requires IE9 or above browsers, the latest Google Chrome and other browsers to support it. Of course, domestic browsers such as 360 Browser, Baidu Browser, and Aoyou Browser all use the IE kernel that comes with the system, so domestic browsers are actually the same version as the IE version that comes with your system, so your IE browser is IE9 or above. The version is naturally compatible with the new tag elements of HTML5.

4. Comparison case of old and new div layout

Observe and master the application of header by comparing div CSS layout and HTML5 CSS layout.

Example

<!DOCTYPE html>
<html>
  <head>
    <meta charset="utf-8" />
    <title>html5 Header标签实例 DIVCSS5</title>
    <style>
      /* 传统布局CSS */
      #header {
        width: 300px;
        height: 40px;
        background: #ccc;
      }

      /* HTML5布局样式 */
      header {
        width: 400px;
        height: 70px;
        color: #f00;
        background: #f5f5f5;
      }
      .color-000 {
        color: #000;
        background: #666;
      }
    </style>
  </head>
  <body>
    <div id="header">我在传统div布局中</div>

    <header>
      我在传统div布局中,必须在支持HTML5浏览器才能看到效果，
      建议谷歌浏览器测试观察效果
    </header>

    <header class="color-000">我颜色为黑色,背景为#666</header>
  </body>
</html>

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Effect screenshot

What does header definition mean in html?

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