Simple comparison: the difference between xml and html

XML and HTML are two different languages ​​that describe text and data in different ways. XML is an extensible markup language, a general-purpose markup language used to represent structured data. HTML is a hypertext markup language primarily used to render text and images in web pages.

Here are some important differences between XML and HTML:

1. Purpose and Application

XML was designed to allow sharing between applications Structure data and provide a common way to describe any type of data. XML is stateless, meaning that any element in an XML document can be processed independently and does not require predefined tags.

HTML is designed to render a complete web page, including text, images, and multimedia. HTML is suitable for displaying information, but not suitable for representing data structures. HTML is stateful, and each element is defined through tags and attributes.

2. Tags and Elements

Both XML and HTML use tags to define elements and attributes, but they have different conventions.

XML requires that all elements and attributes have closing tags, even if they are empty elements. For example, for an empty element, XML uses the following code:

HTML allows the closing tag to be omitted, for example:

HTML's syntax allows developers to create incompatible pages, which is a bad practice, while XML allows any structure to be used, but must follow a prescribed format.

3. Attribute value

In XML, attributes must always be enclosed in quotes, which can be single or double quotes. For example:

In HTML, this rule is not required, but it is usually recommended that attribute values ​​be enclosed in quotes, to ensure the code is easier to read.

4. Predefined entities

There are five predefined entities in XML: <, >, &, ' and ", these entities are used to represent special characters.

HTML has more predefined entities, such as and ©, which are used to display special characters when rendering the page .

5. Namespace

XML supports namespaces, allowing elements and attributes to have the same name but exist in different namespaces, and to avoid name conflicts. HTML There is no concept of namespaces.

Conclusion

XML and HTML differ in both design intent and language conventions. XML is a more general language, suitable for describing any type of structured data .HTML is a language suitable for Web pages that render text, images, and multimedia content. Understanding these differences can help you choose the right language to meet the needs of your application or website.

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