XML (eXtensible Markup Language) is a flexible markup language used for storing and transporting data. Unlike HTML which focuses on presentation, XML focuses on what the data is.

Key characteristics:

• Self-describing: Tags describe the data content
• Platform-independent: Works across all systems
• Human-readable: Easy to understand and debug
• Hierarchical: Data organized in a tree structure
• Extensible: You define your own custom tags

Key XML Components:

• Declaration: <?xml version="1.0"?>
• Root Element: Single top-level element containing all data
• Child Elements: Nested tags within parent elements
• Attributes: <element attr="value">
• Text Content: Data between opening and closing tags
• Comments: <!-- comment -->

• Validate XML syntax
• Format with proper indentation
• Minify XML for compression
• Detect encoding issues
• Line numbers for reference
• Copy and clear functionality
• Works 100% in your browser

• Configuration Files: Store app settings in XML
• Data Exchange: Transfer data between systems
• Web Services: SOAP and REST API responses
• Document Processing: Word, Excel files (OOXML)
• SVG Graphics: Scalable vector graphics
• Data Validation: Schema-based validation

• Use descriptive names: Make tag names meaningful
• Keep it simple: Don't over-nest elements
• Validate schemas: Use XSD for validation
• Consistent formatting: Use proper indentation
• Specify encoding: Always declare XML version
• Escape special chars: Use &, <, > properly

❌ Mismatched Tags

Every opening tag must have a matching closing tag.

❌ Missing Root Element

XML must have exactly one root element wrapping all content.

❌ Special Characters

Characters like <, >, & must be escaped.

❌ Attribute Quotes

Attribute values must always be quoted.