HTML--WWW_html/css_WEB-ITnose

HTML (Hypertext Markup Language, Hypertext Markup Language), I also came into contact with a concept when learning Html??WWW, this is often used, but I don’t know the reason.

Basic concepts

WWW (World Wide Web) is a global, interactive, multi-platform, distributed information resource network built on the Internet. It is a hypertext file (including connection relationships and multimedia objects) described in HTML language.

The URLs we see most, or the URLs we use in memory are probably WWW. WWW has three basic components, namely URL (Universal Resource Locators, Uniform Resource Locator), HTTP (Hypertext Transfer Protocol, Hypertext Transfer Protocol) and HTML (Hypertext Markup Language, Hypertext Markup Language)

URL

URL provides access on the web The unified method and path of resources makes the site that the user wants to visit unique, which is equivalent to each of us having only one ID. It represents the type of each file pointed to by the link and its exact location.

It can also be understood that URL is the only way for you to get the location or access method of a resource. As long as you know the URL of the resource, you can get the address and operate the resource.

There are two access methods for URLs: ftp and http

For example,

🎜>

HTTP

HTTP is a data transmission protocol on the Internet, specifically used to transmit information provided in the form of hypertext (hypertext) or hypermedia (hypermedia) . It is a data transfer protocol that specifies the rules for communication between browsers and World Wide Web servers and transmits World Wide Web documents through the Internet.

HTTP works on the TCP protocol in the TCP/IP protocol system.

Both the client and server must support HTTP in order to send, receive, and interact with HTML documents on the World Wide Web.

(Most of the above are encyclopedia content?? HTTP)

HTML

HTML language is a text-based markup language that relies on interpretation, that is, it uses a most A language that the computer can recognize. The language used on the World Wide Web is generally Html language.

HTML is a markup language, so it will have a lot of markup elements. The most basic file structure is as follows:

So if you want to learn HTML well, it is necessary to have a certain knowledge of markup elements. of. For example, title text tags

	-----------------------------------------------------开始html文档		---------------------------------------------开始文档头部			<title>---------------------------------------开始文档标题				标题---------------------------------内容			</title>-------------------------------------结束文档标题		-------------------------------------------结束文档头部		--------------------------------------------开始文档体			正文----------------------------------------内容		-------------------------------------------结束文档 体	---------------------------------------------------结束html文档

What are HTML4, XHTML, and HTML5

    <title></title>    <h1 id="h-字体大小">h1 字体大小</h1>    <h2 id="h-字体大小">h2 字体大小</h2>    <h3 id="h-字体大小">h3 字体大小</h3>    <h4 id="h-字体大小">h4 字体大小</h4>    <h5 id="h-字体大小">h5 字体大小</h5>    <h6 id="h-字体大小">h6 字体大小</h6>

When I was learning html, there were a lot of html or XHTML when I read other blogs. I don’t know if they just have different names or what’s the difference. Then I checked the information and compared it.

In the early days of HTML development, before the establishment of W3C (World Wide Web Consortium, World Wide Web Consortium), many standards of HTML were very non-standard, and browsers also had requirements for HTML. Not high, so the continuation of this situation has led to HTML writers writing a large number of HTML pages containing errors.

Later, W3C also realized this error and believed that this was a fundamental problem on the Internet and should be solved. In order to standardize HTML, W3C developed the XHTML1.0 standard in combination with XML, but it only uses XML requirements to standardize HTML. You can understand XHTML as HTML XML.

HTML4 is currently the most widely used standard on the Internet. It was born around 1999. It still plays an important role.

HTML5 has some new features: 1. Canvas element for painting 2. Video and audio elements for media playback 3. Better local offline storage Support 4. New special content elements, such as article, footer, header, nav, section 5. New form controls, such as calendar, date, time, email, url, search. One of its biggest features is that it will not break existing web pages. Although HTML5 adds many new features, it is not universally supported by browsers, so other HTML is still important and still in use.

Here is a very interesting comic. If you are interested, you can read "Chaos Markup Language XHTML2/HTML5 Comic"

Reference blog: http://autit.blog.163.com/blog/static/13804284420125710238652/