Introduction

Here is the Introduction of XML:

XML, or eXtensible Markup Language, is a markup language that defines a set of rules for encoding documents in a format that is both human-readable and machine-readable.

• It is often used to represent structured data and to exchange information between systems over the internet

• It is a software- and hardware-independent tool for storing and transporting data.

• It is a markup language much like HTML

• XML documents have a hierarchical structure, organized as a tree.

• The “X” in XML stands for extensible. This means that you can define your own tags and attributes to represent data in a way that is meaningful for your specific application or domain.

Note: XML is a markup language similar to HTML (Hypertext Markup Language). However, while HTML is designed to display data, XML is designed to store and transport data.

Difference between XML and HTML:

XML Syntax Rules

XML documents must contain one root element that is the parent of all other elements:

<root>
  <child>
    <subchild>.....</subchild>
  </child>
</root>

Example:-

<root>
  <person>
    <details>Personal Information</details>
    <name>John Doe</name>
    <age>30</age>
    <address>
      <street>Main Street</street>
      <city>City</city>
      <country>Country</country>
    </address>
  </person>
</root>

Comments in XML

The syntax for writing comments in XML is similar to that of HTML:

<root>
  < !-- This is a comment -- >
  <child>
    <! -- Comments can be added anywhere in the XML document -- >
    <subchild>This is some content</subchild>
  </child>
</root>

Structure of XML

The structure of an XML file consists of elements organized in a hierarchical manner. Each XML file must have a single root element that encloses all other elements.

• Elements can contain text, attributes, and other elements, forming a tree-like structure.

<?xml version="1.0" encoding="UTF-8"?>
<library>
    <book ISBN="978-3-16-148410-0">
        <title>XML Basics</title>
        <author>John Doe</author>
        <publication_year>2020</publication_year>
    </book>
    <book ISBN="978-3-16-148411-7">
        <title>Advanced XML</title>
        <author>Jane Smith</author>
        <publication_year>2021</publication_year>
    </book>
</library>