What does the abbreviation XML mean?

Files with the .xml extension keep popping up on the World Wide Web and offline. But what does this abbreviation mean? The Extensible Markup Language (XML for short) structures hierarchies in files by means of tags. Two tags or markers each contain one element. To illustrate this, I am an example . Bracket notation is used to divide the entire text into its respective sections and provide an overview. An XML element consists of its tags, text and attributes. The latter differs from plain text in that the content is enclosed in quotes and also describes a category.

The metalanguage is not encoded in binary, but is composed of plain text characters. Often this is ASCII encoding and thus human and machine readable. The property of extensibility represents one of the major differences to HTML. The latter meta language is only suitable for documents on the Internet and is strongly oriented towards written elements. XML, on the other hand, is extensible and has no definitive vocabulary. Temporal information, security elements, and even graphical components, among others, can be captured in XML.

What is the advantage in the files of XML? The text files, in addition to the extensibility already mentioned, offer an indispensable independence. On the one hand the data exchange can take place platform-spreading and is not bound to the respective implementation for this. Specific sublanguages can be developed on the basis of XML, depending on the application. In order to maintain a certain unity for the data exchange, the sentence structure and semantics via a document type definition (DTD for short) or another schema language is recommended. These rules ensure a consistent structure across a wide variety of files.

XML is the base language for numerous other W3C standards. Es existieren beispielsweise Abfragesprachen wie XPath oder XQuery und eine Transformationssprache (XSLT). Die wichtige Weiterentwicklung von HTML basiert ebenso auf XML (XHTML). Die Sprache ist zudem die Grundlage der wichtigsten Standards von Web-Services (beispielsweise SOAP, WSDL, und BPEL4WS) und der Sprachen des semantischen Webs (beispielsweise RDF und OWL).

Weitere Informationen zum Thema finden Sie hier.