The role of the meta tag in HTML: 1. Search engine optimization (SEO); 2. Define the encoding used by the page; 3. Automatically refresh and point to the new page; 4. Realize dynamic effects during web page conversion; 5. , control page buffering; 6. web page rating and evaluation; 7. control the window for web page display, etc.

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

Meta summary of html

The composition of meta tag: meta tag has two attributes, they are http-equiv attribute and name attribute, different attributes are Different parameter values, these different parameter values ​​realize different web page functions.

meta tag has the following functions:

1. Search engine optimization (SEO)

2. Define the encoding used by the page

3. Automatically refresh and point to the new page

4. Achieve dynamic effects during web page conversion

5. Control page buffering

6. Web page rating evaluation

　7. Window that controls web page display

1. Name attribute

The name attribute is mainly used to describe the web page. The corresponding attribute value is content. The content in content is mainly It is convenient for search engine robots to find and classify information.

The syntax format of the name attribute of the meta tag is:

<meta name="参数"content="具体的参数值">。

The name attribute mainly has the following parameters:

A, Keywords (keywords)

Description: keywords are used to tell search engines what the keywords of your web page are.
Example:

<meta name="keywords"content="meta总结,html meta,meta属性,meta跳转">

B. description (website content description)

Description: description is used to tell search engines the main content of your website.
Example:

<meta name="description"content="haorooms博客,html的meta总结，meta是html语言head区的一个辅助性标签。">

C, robots (robot guide)

Description: robots are used to tell the search robot which pages need to be indexed and which pages do not need to be indexed.

The parameters of content include all, none, index, noindex, follow, and nofollow. The default is all.

Example:

<meta name="robots"content="none">

The specific parameters are as follows:

• The information parameter is all: the file will be retrieved, and the links on the page can be queried;

• The information parameter is none: the file will not be retrieved, and the links on the page cannot be queried;

• The information parameter is index: The file will be retrieved;

• The information parameter is follow: the links on the page can be queried;

• The information parameter is noindex: the file will not be retrieved, but the links on the page can be queried;

• The information parameter is nofollow: the file will be retrieved, but the links on the page cannot be queried;

D、author(author)

Description: Mark the author of the web page

Example:

<meta name="author"content="root,root@xxxx.com">

E、generator

<meta name="generator"content="信息参数"/>

meta The information parameter of the tag's generator represents the software used to create the website.

F. COPYRIGHT

<META NAME="COPYRIGHT"CONTENT="信息参数">

The COPYRIGHT information parameter of the meta tag represents website copyright information.

G, revisit-afte

<META name="revisit-after"CONTENT="7days">

revisit-after represents website revisit, 7days represents 7 days, and so on.

2. http-equiv attribute

http-equiv, as the name suggests, is equivalent to the file header function of http. It can return some useful information to the browser to help display it correctly and accurately. Web page content, the corresponding attribute value is content, and the content in content is actually the variable value of each parameter. The syntax format of the http-equiv attribute of the

meta tag is:

; The http-equiv attribute mainly has the following parameters:

A, Expires (period)

Description: It can be used to set the expiration time of the web page. Once a web page expires, it must be retransmitted to the server.
Usage:

<meta http-equiv="expires"content="Fri,12Jan200118:18:18GMT">

Note: GMT time format must be used.

B. Pragma (cache mode)

Description: Prohibit the browser from accessing page content from the cache of the local computer.

Usage:

<meta http-equiv="Pragma"content="no-cache">

Note: With this setting, visitors will not be able to browse offline.

C. Refresh(refresh)

Description: Automatically refresh and point to the new page.

Usage:

<meta http-equiv="Refresh"content="2;URL=http://www.haorooms.com"> //(注意后面的引号，分别在秒数的前面和网址的后面)

Note: The 2 refers to automatically refreshing to the URL after staying for 2 seconds.

D. Set-Cookie (cookie setting)

Note: If the web page expires, the saved cookies will be deleted.

Usage:

<meta http-equiv="Set-Cookie"content="cookie value=xxx;expires=Friday,12-Jan-200118:18:18GMT；path=/">

Note: GMT time format must be used.

E. Window-target (display window setting)

Description: Force the page to be displayed as an independent page in the current window.

Usage:

<meta http-equiv="Window-target"content="_top">

Note: Used to prevent others from calling your own page in the frame.

F, content-Type (display character set setting)

Description: Set the character set used by the page.

Usage:

<meta http-equiv="content-Type"content="text/html;charset=gb2312">

The details are as follows:

• meta标签的charset的信息参数如GB2312时，代表说明网站是采用的编码是简体中文；

• meta标签的charset的信息参数如BIG5时，代表说明网站是采用的编码是繁体中文；

• meta标签的charset的信息参数如iso-2022-jp时，代表说明网站是采用的编码是日文；

• meta标签的charset的信息参数如ks_c_5601时，代表说明网站是采用的编码是韩文；

• meta标签的charset的信息参数如ISO-8859-1时，代表说明网站是采用的编码是英文；

• meta标签的charset的信息参数如UTF-8时，代表世界通用的语言编码；

G、content-Language（显示语言的设定）

用法：

<meta http-equiv="Content-Language"content="zh-cn"/>

H、http-equiv="imagetoolbar"

<meta http-equiv="imagetoolbar"content="false"/>

指定是否显示图片工具栏，当为false代表不显示，当为true代表显示。

J、Content-Script-Type

<Meta http-equiv="Content-Script-Type"Content="text/javascript">

W3C网页规范，指明页面中脚本的类型。

L 页面跳转，只用于IE

推荐教程：《html视频教程》

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