What is the difference between xhtml html4 and html5?

Related questions

1. Is it necessary to write doctype in HTML?
2. Why doctype html is needed?
3. Why xhtml is needed?
4. How xhtml is more advantageous than HTML?
5. What is xhtml Why is xhtml needed?
6. Who made HTML 5?
7. What is the w3c what is the Whatwg quizlet?
8. How xhtml is different from HTML?
9. Is html and xhtml the same?
10. Which is better xhtml or html5?

Tags

1. #html4
2. #xhtml
3. #stands
4. #closed
5. #between
6. #hypertext
7. #specific
8. #dialect
9. #actually
10. #opened
11. #markup
12. #which
13. #language
14. #difference
15. #aside
16. #generalised
17. #extensible