<Head>…</head> means the file header of <HTML>, which is used to explain the file naming and related information about the file itself. Usually this part of the tag declares this web page: default language encoding, keywords, software usage, etc.
Meta tags can be divided into two parts: HTTP title information (HTTP-EQUIV) and page description information (NAME). The following table describes HTTP header information.
Table 1 HTTP title information (HTTP-EQUIV) table
| content-type | Show character set | <Meta http-equiv=content-type content =text/html;charset=GB2312> |
| Refresh | Let the page refresh itself at a specified time, or jump | <Meta http-equiv=refresh content=30;url=http://weibo.com/jjseen> |
| Expires | Specify the expiration time of the web cache | <Meta http-equiv=expires content=0> <!-- Expired soon--> |
| cache | Whether to allow browsers to view caches from local machines | <Meta http-equiv=cach content=NO-cach> <!--Prohibited, web page is not saved, refresh every time you access--> |
| set-cookie | Whether to disable cookies or invalidate cookies | <Meta http-equiv=set-cookie content=cookievalue=××;expires=Wednesday,21…/> |
| window-target | How to display the page | <Meta http-equiv=window-target content=_top/> Force the page to be displayed as a separate page in the current window, which can also be used to prevent others from calling the page in the framework. The options for content are _blank,_top,_self,_parent. |
| page-enter, page-exit | Special effects settings for entering and exiting pages | <Meta http-equiv=page-enter content=blendTrans(Duration=0.5)> This actually uses the CSS filter. |
Meta's page description information (NAME) is used to describe and describe web pages. Name is used to describe web pages and corresponds to contents for easy search and classification of search robots. The value of name (name=) specifies the type of information provided, some of which are
Values are already defined, such as description, keyword, refresh, etc. You can also specify any other arbitrary values, such as creationdate, documentID, Level, etc. The following table is the specific syntax:
Table 2 HTTP description information table
| keywords | Declare the keywords of the web page, and the search engine automatically completes the keyword index. | <Meta name=keywords content=HTML,HTML header,HTTP-EQUIV,meta/> |
| Description | Describe the main content of the website, and search Yinqin will also search the website through this attribute, but it will not be displayed. | <Meta name=Description content=This blog post explains the tags related to HTML headers/ |
| Robots | Robot Wizard, used to tell the robot which pages need indexes and which do not need indexes. | <Meta name=Robots contents=All|None|Index|Noindex|Follow|NoFollow> all: The file will be indexed. The None file is not indexed, and the links on the page cannot be queried. (It has the same effect as NoIndex and NoFollow).Index: The file will be retrieved. Follow: The link on the page can be queried. |
| Author | Page Author | <Meta name=Author content=jjseen,[email protected]/> |
| Copyright | Used to mark copyright | <Meta name=Copyrightng content=Copyrightng/ |
| Generator | Editor | |
| revisit-after | Sets the time interval for revisiting, in days. (I'm not sure what the label does) | <Meta name=revisit-after content=7 days> |
Meta has some other tags, which are also sorted out, see the table below:
Table 3 Meta Other Tags
| scheme | A meaning tag for explaining content | <Meta scheme=ISBN name=identifier content=0-14-042152> |
| link | Link to a file | <link href=logo.ico rel=Shortcut Icon> The small icon displayed after putting it in your favorites, the small icon on the address bar |
| base | Basic link | <base href=http://weibo.com/jjseen target=_blank>After using this statement, all relative paths on the web page will automatically add the previous address when linked. |