The difference between XML and HTML

I believe many students are confused about the difference between html and xml, right? Today let us take a look at the difference between html and xml, and what is the difference in syntax between html and xml.

1. What is HTML? .

2. What is XML Language, its predecessor is SGML (Standard General Markup Language). It has no tagset (tagset) and no grammatical rule (grammatical rule), but it has syntax rule (syntax rule). Any XML document must be well-formed for any type of application and correct parsing, that is, each open tag must have a matching closing tag, must not contain tags in reverse order, and have good statement composition. Should meet the requirements of technical specifications. An XML document can be valid, but it does not necessarily need to be valid. A valid document is a document that conforms to its document type definition (DTD). A document is schema valid if it conforms to the provisions of a schema.

3. The difference between HTML and XML

Through the above understanding of HTML and XML, let’s take a look at the differences and connections between themxml and html are both used to manipulate data or data structures. They are roughly the same in structure, but there are obvious differences in their essence.

(1) Different grammatical requirements:

1. There is no case sensitivity in html , strictly distinguished in xml. 2. In HTML, sometimes it is not strict. If the context clearly shows where the paragraph or list key ends, then you can omit the ending like

or mark. In XML, it is a strict tree structure, and the closing tag must not be omitted.

3. In XML, elements that have a single tag without a matching closing tag must end with a / character. This way the parser knows not to look for the closing tag. 4. In XML, the

attribute

value must be enclosed in quotation marks. In HTML, quotation marks are optional.

5. In HTML, you can have attribute names without values. In XML, all attributes must have corresponding values.

6. In the XML document, the blank parts will not be automatically

removed

by the parser; but html filters out the blanks.

(2) Different tags:

1. HTML uses inherent tags; xml does not have inherent tags. 2,

Html tag

is predefined; XML tag is free, customizable and extensible.

(3) Different functions:

1. HTML is used to display data; xml is used to describe data and store data, so it can be used as a persistence medium! Html combines data and display and displays the data on the page; xml

separates data and display. XML is designed to describe data, and its focus is the content of the data. HTML was designed to display data, with the focus being on the appearance of the data.

2. XML is not a substitute for HTML. XML and HTML are two languages ​​with different uses. XML is not meant to replace HTML; in fact, XML can be seen as a complement to HTML. The goals of XML and HTML are different. The design goal of HTML is to display data and focus on the appearance of the data, while the design goal of XML is to describe the data and focus on the content of the data.

3. XML without any behavior. Similar to HTML, XML does nothing. (Common ground)

4. The best description of XML may be: XML is a cross-platform, software- and hardware-independent tool for processing and transmitting information.

5. XML will be everywhere in the future. XML will become the most common tool for data processing and data transmission.

The above is all the content of this article. I hope it can help everyone and let everyone have a deeper understanding of html and xml

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