1. HTML tag
declaration must be the first line of the HTML document, located at before label.
The declaration is not an HTML tag; it is an instruction to the web browser as to which version of HTML the page should be written in.
In HTML 4.01, the declaration references a DTD because HTML 4.01 is based on SGML. A DTD specifies the rules for a markup language so that browsers can render content correctly.
HTML5 is not based on SGML, so there is no need to reference a DTD.
Tip: Always add the declaration to your HTML document so the browser knows the document type.
2. Problems with the tags charset=gb2312 and charset=utf-8 in the HTML language
charset = gb2312 is Simplified Chinese, UTF-8 is International coding, if you are in China, it is best to use gb2312, which will be faster. It is not easy to produce garbled characters
3. meta name="description" content="Here is the description of the web page, which is for search engines to see. The search engine will rank the inclusion and ranking based on this description. Generally, are keywords within the web page. The
element provides meta-information about the page, such as description and keywords for search engines and update frequency. The tag is located at the head of the document and contains no content. The properties of the tag define the name/value pairs associated with the document.
4
,This code is the verification code for Baidu Webmaster Platform to verify website ownership.
5
, tagdefines the relationship between the document and external resources. The most common use of the tag is to link style sheets. , the tag has no closing tag. In XHTML, the tag must be closed correctly. Example:
Links to an external style sheet. :
Explanation rel: Specifies the relationship between the current document and the linked document.
The href attribute of the tag is used to specify the URL of the hyperlink target. > The value of the href attribute can be a relative or absolute URL to any valid document, including fragment identifiers and JavaScript snippets. If the user selects content within the tag, the browser will attempt to retrieve and display the content specified by the href attribute. The document represented by the URL, or a list of JavaScript expressions, methods and functions.
*Possible values:
Absolute URL - pointing to another site (such as href ="http://www.example.com/index.htm")
Relative URL - points to a file within the site (href="index.htm")
<head><link rel="stylesheet" type="text/css" href="theme.css" /></head>
6.
charset=utf-8
Indicates that the character set of the current document uses utf-8 characters, which is what we It is often said that the English character set;charset
is Unicode Translation Format, which means converting Unicode into a certain format. gbk gb2312
Mainly used in Chinese. big5
for Traditional Chinese