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XML Design Principles

1. XML shall be straightforwardly usable over the Internet.

     Web basis suits limited bandwidth & diverse clients.

2. XML shall support a wide variety of applications.

     XML's innate extensibility provides this.

3. XML shall be compatible with SGML.

     Enables SGML tools to interpret XML from valid DTD.

4. It shall be easy to write programs which process XML documents.

     Requires tag pair enclosures, DTDs read before markup or
     entities are referenced, and validation & completeness rules.

5. Keep options in XML to absolute minimum, ideally zero.

     Seldom used options made SGML costly to implement.

6. XML documents should be human-legible and reasonably clear.

     Both humans and computers need to read and write XML.

7. XML design should be prepared quickly.

     Working group achieved good results in just over a year.

8. The design of XML shall be formal and concise.

     SGML spec is 500 pages. XML spec is 60 (7 for syntax).

9. XML documents shall be easy to create.

     Easy creation better guarantees tool vendor support.

10. Terseness in XML markup is of minimal importance.

     Clear, intelligible markup is better than terse or cryptic.

See What's the point of XML?, Tittel E, Sun World Online, Feb 1998