What's wrong with HTML?
- HTML was optimized for easy learning
- One tag set for all applications
- Predefined semantics for each tag
- Predefined data structures
- No formal validation
- Poor support for nested structures
- HTML trades power for ease of use
- HTML is well suited to simple applications
- Poorly suited to more demanding applications
- Large or complex collections of data
- Complex structured data
- Data that must be used in different ways
- Data with a long life cycle
