1. Introduction to Html_html/css_WEB-ITnose

What is html?

hypertext markup language. Hypertext Markup Language is an application under the Standard Universal Markup Language. It is also a specification and a standard. It uses markup symbols to mark various parts of the web page to be displayed. The web page file itself is a text file. By adding tags to the text file, you can tell the browser how to display the content (such as how to process text, how to arrange pictures, how to display pictures, etc.). The browser reads the web page files in order, and then interprets and displays the marked content according to the tags. The error will not be pointed out for wrongly written tags, and the interpretation and execution process will not be stopped. The compiler can only analyze the cause of the error through the display effect. and error location. However, it should be noted that different browsers may not have exactly the same interpretation of the same tag, and thus may have different display effects.

The format of the HTML tag consists of:
ELEMENT: element - identification tag
ATTRIBUTE: attribute - description tag
value: value - assigned to the attribute The content of

The above definition was found in Baidu Encyclopedia. To put it simply, html is the document tree of the page. We write an html file with many tags, and the browser interprets these tags and then displays a web page to us. Learning HTML is much simpler than learning the Java programming language. We only need to remember various HTML tags and embed them into ordinary text.

There are two points to note about the definition of html:

1. When we define an html file in the future, do not use htm as the suffix, but use the suffix html.

2. What I am dealing with here is XHTML, which is stricter and purer HTML. I have already written about XML, HTML, and XHTML3 in a blog. What I am organizing here is XHTML. In the future, we must abide by these specifications and do not write html files casually. One point that is particularly noteworthy is that XHTML must first be an XML document, and all basic rules of XML must be followed. In addition, XHTML also requires that all tag names be in lowercase letters.

Add another knowledge point:

XML document is a structured document, which has the following 5 basic rules:
1. The only root element
2. Elements must have start tags and end tags, appearing in pairs
3. Correct nesting relationship of elements
4. Tags are case-sensitive
5. Attributes must have a value, and the value must be enclosed in quotes Come