Is html xml?

html is not xml. HTML refers to Hypertext Markup Language, which is the description language of WWW; while XML refers to Extensible Markup Language, which is a metalanguage used to define other languages. HTML is not case-sensitive, while XML is case-sensitive.

The operating environment of this tutorial: Windows 7 system, HTML5 version, Dell G3 computer.

html is not xml.

HTML (HyperTextMark-upLanguage) is Hypertext Markup Language, which is the description language of WWW.

XML is Extensible Markup Language (Extensible Markup Language), which is a meta-language used to define other languages. Its predecessor is SGML (Standard General Markup Language). It has no tagset and no grammatical rules, but it has syntax rules. 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.

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 them

Both xml and html are used to manipulate data or data structures. They are roughly the same in structure, but there are obvious differences in their essence. A summary of various information available online is as follows.

(1) Different grammatical requirements:

1. Case-insensitive in html, but strictly 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, attribute values ​​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 XML documents, the blank parts will not be automatically deleted 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 tags are predefined; XML tags are 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, with the focus being 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 intended 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. Like 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.

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