What is "xml" and how to use it?

Category: Computer/Network>gt; Internet

Analysis:

Just like HTML, so is XML (eXtensible Markup Language) A markup language. It also relies on tags describing certain rules and application processing tools that can read these tags to exert its powerful functions. This can also be seen from the naming of XML.

"The correct title for this specification, the correct full name for XML, is Extensible Markup Language. eXtensible Markup Language is just a misspelling. However, the abbreviation XML is now not only correct, but also just like It is the official name of Extensible Markup Language as it appears in the title of this specification.

This name and abbreviation were first proposed by James Clark. Other alternative names include Small Standard Markup Language. MGML (Minimal Generalized Markup Language), MAGMA (Minimal Architecture For Generalized Markup Applications), and SLIM (Structured Language for Inter Markup)

——Extensible. Markup Language (XML) 1.0 Specs, The Annotated Version. ”

From the original naming of XML, we can see that the core of XML is markup in the final analysis. However, XML, a markup language, is much more powerful than HTML.

"人" is as its name suggests, and the powerful functions of XML come from "X". In other words, XML is not only a markup language, but also an extensible (eXtensible) markup language. XML does not provide a set of pre-defined tags like HTML, but provides a standard. Using this standard, you can define your own new markup language according to actual needs, and provide your own markup language. A language specifies its own unique set of labels. To be precise, XML is a source markup language that allows you to develop a variety of markup languages ??based on the rules it provides. This is also the original goal of the XML language.

"The development goals of XML are:

XML should be able to be used directly on the Internet (*as easy to use as HTML).

XML should support various Different application methods (*including not only browsing, but also analysis of content).

XML should be compatible with SGML (*Inheriting from father's legacy, we will talk about it later, SGML is a direct descendant of XML. Pioneer).

Applications that process XML files should be easy to write (*should take a computer science graduate student two weeks to do).

Optional features in XML. The number should be reduced to a minimum, preferably to none (*optional features often cause confusion)

XML files should be readable and relatively clear (*not like HTML, if Reading it without a browser is a test of your willpower and patience)

Designing a new markup language using XML should be quick and easy (you no longer have to go through the tedious process of standards development). ).

The markup language designed for XML should be formal and concise (otherwise, how can it be easy to write and read?).

XML files should be easy to compile (think about how terrible it is to write HTML using "Notepad").

The simplicity of the XML markup doesn't matter (you don't have to worry about reducing the markup).

——Extensible Markup Language (XML) 1.0 Specs, The Annotated Version."