What Is XML?

Date First Published: 23rd October 2022

Topic: Web Design & Development

Subtopic: Web Development

Article Type: Computer Terms & Definitions

Difficulty: Medium

Difficulty Level: 5/10

CONTENTS

Difference Between XML and HTML

Learn more about what XML is in this article.

Stands for Extensible Markup Language. XML is a markup language used for storing and transmitting data. XML stores data in a plain text and structured format between tags, providing a format that is compatible with a wide range of operating systems, web browsers, applications, and systems, and is both human-readable and machine-readable. XML is not a programming language. It is a data format that can be used to specify items that may be transmitted between a page and a web server. XML became a W3C recommendation as early as in February 1998. An example of an XML document can be seen below:

<?xml version="1.0" encoding="utf-8"?>

<title>Computerhelp4all RSS Feeds</title>

<description>Computer help, Computer tricks, IT help</description>

<item>

<title>What Is Direct Traffic?</title>

<guid>https://computerhelp4all.com/articles/what-is-direct-traffic.html</guid>

<description>Direct traffic is defined as traffic with no referring website or source.</description>

<category>Web Design & Development</category>

</item>

<item>

<title>What Is Organic Traffic?</title>

<guid>https://computerhelp4all.com/articles/what-is-organic-traffic.html</guid>

<description>Organic traffic describes traffic that comes through search engines.</description>

<category>Web Design & Development</category>

</item>

<item>

<title>What Is The Golden Ratio?</title>

<guid>https://computerhelp4all.com/articles/what-is-the-golden-ratio.html</guid>

<description>The golden ratio, also known as the golden rectangle or divine ratio, is a special formula.</description>

<category>Web Design & Development</category>

</item>

</channel>

</rss>

The XML document above specifies the data for an RSS feed. When read by an RSS reader, the reader will use the text to display the content of each RSS feed, including the title, URL, description, category, date published, and language. Similar to how web browsers render HTML, it will not display the tags. Each tag in an XML document must have an opening and closing tag. Closing tags include a forward slash, such as </channel>. The XML declaration tag at the top is required if the encoding of the document is anything other than UTF-8 or UTF-16.

XML files can be identified by the file extension '.xml'. They can be opened with any application that is capable of reading text files, but it is easier to create an XML file using an editor that highlights the XML syntax, such as Notepad++ or Adobe Dreamweaver.

Difference Between XML and HTML

The main difference between XML and HTML is that XML has no predefined tags that are defined in any XML standard. The tags are invented by the author, which is the reason why XML is extensible. XML can be extended or customised from its original state in order to make it appropriate for the tasks that need to be performed with it. HTML works with predefined tags, such as <h1>, <h2>, and <p>. XML was designed to carry data with a focus on what data is and HTML was designed to display data with a focus on the look and appearance of data. Another difference is that XML tags are case-sensitive, whilst HTML tags are not case-sensitive.

XML has strict validation, which means that any errors in the code will cause the whole file to fail when processed for output. It is necessary for users to always ensure that their XML code has no errors and to fix any before it goes live. Errors in HTML code will cause the specific element to stop working, but not the entire document.

Use this to link to this article:

HTML: <a href="https://computerhelp4all.com/articles/what-is-xml.html">Computerhelp4all</a>

Plain link: https://computerhelp4all.com/articles/what-is-xml.html