What is the difference between HTML xhtml and html5?

Related questions

1. What is xhtml explain?
2. What is the new features of html5?
3. Why should I learn html5?
4. What is the advantage of html5 semantic tags?
5. What is the main difference between HTML and html5?
6. What are the new features in css3?
7. What is difference between html4 and html5?
8. What can be done with html5?
9. What are the features of css3?
10. Why xhtml is used?

Tags

1. #html5
2. #lenient
3. #compatible
4. #html4
5. #sensitive
6. #doctypes
7. #insensitive
8. #doctype
9. #browsers
10. #following
11. #while
12. #xhtml
13. #footsteps
14. #simpler
15. #interpret
16. #browser